Space-Time Crystal and Space-Time Group.
Xu, Shenglong; Wu, Congjun
2018-03-02
Crystal structures and the Bloch theorem play a fundamental role in condensed matter physics. We extend the static crystal to the dynamic "space-time" crystal characterized by the general intertwined space-time periodicities in D+1 dimensions, which include both the static crystal and the Floquet crystal as special cases. A new group structure dubbed a "space-time" group is constructed to describe the discrete symmetries of a space-time crystal. Compared to space and magnetic groups, the space-time group is augmented by "time-screw" rotations and "time-glide" reflections involving fractional translations along the time direction. A complete classification of the 13 space-time groups in one-plus-one dimensions (1+1D) is performed. The Kramers-type degeneracy can arise from the glide time-reversal symmetry without the half-integer spinor structure, which constrains the winding number patterns of spectral dispersions. In 2+1D, nonsymmorphic space-time symmetries enforce spectral degeneracies, leading to protected Floquet semimetal states. We provide a general framework for further studying topological properties of the (D+1)-dimensional space-time crystal.
Ishak, Siti Nor Hasmah; Aris, Sayangku Nor Ariati Mohamad; Halim, Khairul Bariyyah Abd; Ali, Mohd Shukuri Mohamad; Leow, Thean Chor; Kamarudin, Nor Hafizah Ahmad; Masomian, Malihe; Rahman, Raja Noor Zaliha Raja Abd
2017-09-25
Less sedimentation and convection in a microgravity environment has become a well-suited condition for growing high quality protein crystals. Thermostable T1 lipase derived from bacterium Geobacillus zalihae has been crystallized using the counter diffusion method under space and earth conditions. Preliminary study using YASARA molecular modeling structure program for both structures showed differences in number of hydrogen bond, ionic interaction, and conformation. The space-grown crystal structure contains more hydrogen bonds as compared with the earth-grown crystal structure. A molecular dynamics simulation study was used to provide insight on the fluctuations and conformational changes of both T1 lipase structures. The analysis of root mean square deviation (RMSD), radius of gyration, and root mean square fluctuation (RMSF) showed that space-grown structure is more stable than the earth-grown structure. Space-structure also showed more hydrogen bonds and ion interactions compared to the earth-grown structure. Further analysis also revealed that the space-grown structure has long-lived interactions, hence it is considered as the more stable structure. This study provides the conformational dynamics of T1 lipase crystal structure grown in space and earth condition.
Crystal structure and magnetic susceptibility of UOSe single crystals
International Nuclear Information System (INIS)
Kaczorowski, D.; Muenster Univ.; Poettgen, R.; Jeitschko, W.; Gajek, Z.; Zygmunt, A.
1993-01-01
The crystal structure and magnetic susceptibility behaviour of UOSe single crystals have been studied. UOSe crystalizes in the tetragonal PbFC1-type structure (space group P4/nmm) with the lattice parameters: a = 390.38(5) pm and c = 698.05(9) pm. It orders antiferromagnetically at T N =100±2 K and exhibits a very strong anisotropy in the susceptibility vs temperature variation. The magnetic and thermodynamic properties of UOSe are successfully interpreted in the framework of a perturbative ab initio crystal field approach. (Author)
Crystal structure and magnetic susceptibility of UOSe single crystals
Energy Technology Data Exchange (ETDEWEB)
Kaczorowski, D. (Polish Academy of Sciences, Wroclaw (Poland). Inst. for Low Temperature and Structure Research Muenster Univ. (Germany). Anorganisch-Chemisches Inst.); Poettgen, R.; Jeitschko, W. (Muenster Univ. (Germany). Anorganisch-Chemisches Inst.); Gajek, Z.; Zygmunt, A. (Polish Academy of Sciences, Wroclaw (Poland). Inst. for Low Temperature and Structure Research)
1993-01-01
The crystal structure and magnetic susceptibility behaviour of UOSe single crystals have been studied. UOSe crystalizes in the tetragonal PbFC1-type structure (space group P4/nmm) with the lattice parameters: a = 390.38(5) pm and c = 698.05(9) pm. It orders antiferromagnetically at T[sub N]=100[+-]2 K and exhibits a very strong anisotropy in the susceptibility vs temperature variation. The magnetic and thermodynamic properties of UOSe are successfully interpreted in the framework of a perturbative ab initio crystal field approach. (Author).
Habash, Jarjis; Boggon, Titus J; Raftery, James; Chayen, Naomi E; Zagalsky, Peter F; Helliwell, John R
2003-07-01
Models of apocrustacyanin C(1) were refined against X-ray data recorded on Bending Magnet 14 at the ESRF to resolutions of 1.85 and 2 A from a space-grown and an earth-grown crystal, respectively, both using vapour-diffusion crystal-growth geometry. The space crystals were grown in the APCF on the NASA Space Shuttle. The microgravity crystal growth showed a cyclic nature attributed to Marangoni convection, thus reducing the benefits of the microgravity environment, as reported previously [Chayen et al. (1996), Q. Rev. Biophys. 29, 227-278]. A subsequent mosaicity evaluation, also reported previously, showed only a partial improvement in the space-grown crystals over the earth-grown crystals [Snell et al. (1997), Acta Cryst. D53, 231-239], contrary to the case for lysozyme crystals grown in space with liquid-liquid diffusion, i.e. without any major motion during growth [Snell et al. (1995), Acta Cryst. D52, 1099-1102]. In this paper, apocrustacyanin C(1) electron-density maps from the two refined models are now compared. It is concluded that the electron-density maps of the protein and the bound waters are found to be better overall for the structures of apocrustacyanin C(1) studied from the space-grown crystal compared with those from the earth-grown crystal, even though both crystals were grown using vapour-diffusion crystal-growth geometry. The improved residues are on the surface of the protein, with two involved in or nearby crystal lattice-forming interactions, thus linking an improved crystal-growth mechanism to the molecular level. The structural comparison procedures developed should themselves be valuable for evaluating crystal-growth procedures in the future.
Synthesizing lattice structures in phase space
International Nuclear Information System (INIS)
Guo, Lingzhen; Marthaler, Michael
2016-01-01
In one dimensional systems, it is possible to create periodic structures in phase space through driving, which is called phase space crystals (Guo et al 2013 Phys. Rev. Lett. 111 205303). This is possible even if for particles trapped in a potential without periodicity. In this paper we discuss ultracold atoms in a driven optical lattice, which is a realization of such a phase space crystals. The corresponding lattice structure in phase space is complex and contains rich physics. A phase space lattice differs fundamentally from a lattice in real space, because its coordinate system, i.e., phase space, has a noncommutative geometry, which naturally provides an artificial gauge (magnetic) field. We study the behavior of the quasienergy band structure and investigate the dissipative dynamics. Synthesizing lattice structures in phase space provides a new platform to simulate the condensed matter phenomena and study the intriguing phenomena of driven systems far away from equilibrium. (paper)
International Nuclear Information System (INIS)
Beckman, S.P.; Chelikowsky, James R.
2007-01-01
The structure and properties of vacancies in a 2 nm Si nano-crystal are studied using a real space density functional theory/pseudopotential method. It is observed that a vacancy's electronic properties and energy of formation are directly related to the local symmetry of the vacancy site. The formation energy for vacancies and Frenkel pair are calculated. It is found that both defects have lower energy in smaller crystals. In a 2 nm nano-crystal the energy to form a Frenkel pair is 1.7 eV and the energy to form a vacancy is no larger than 2.3 eV. The energy barrier for vacancy diffusion is examined via a nudged elastic band algorithm
Crystal manyfold universes in /AdS space
Kaloper, N.
2000-02-01
We derive crystal braneworld solutions, comprising of intersecting families of parallel /n+2-branes in a /4+n-dimensional /AdS space. Each family consists of alternating positive and negative tension branes. In the simplest case of exactly orthogonal families, there arise different crystals with unbroken /4D Poincaré invariance on the intersections, where our world can reside. A crystal can be finite along some direction, either because that direction is compact, or because it ends on a segment of /AdS bulk, or infinite, where the branes continue forever. If the crystal is interlaced by connected /3-branes directed both along the intersections and orthogonal to them, it can be viewed as an example of a Manyfold universe proposed recently by Arkani-Hamed, Dimopoulos, Dvali and the author. There are new ways for generating hierarchies, since the bulk volume of the crystal and the lattice spacing affect the /4D Planck mass. The low energy physics is sensitive to the boundary conditions in the bulk, and has to satisfy the same constraints discussed in the Manyfold universe. Phenomenological considerations favor either finite crystals, or crystals which are infinite but have broken translational invariance in the bulk. The most distinctive signature of the bulk structure is that the bulk gravitons are Bloch waves, with a band spectrum, which we explicitly construct in the case of a /5-dimensional theory.
Zhang, Min; Liang, Zuozhong; Wu, Fei; Chen, Jian-Feng; Xue, Chunyu; Zhao, Hong
2017-06-01
We selected the crystal structures of ibuprofen with seven common space groups (Cc, P21/c, P212121, P21, Pbca, Pna21, and Pbcn), which was generated from ibuprofen molecule by molecular simulation. The predicted crystal structures of ibuprofen with space group P21/c has the lowest total energy and the largest density, which is nearly indistinguishable with experimental result. In addition, the XRD patterns for predicted crystal structure are highly consistent with recrystallization from solvent of ibuprofen. That indicates that the simulation can accurately predict the crystal structure of ibuprofen from the molecule. Furthermore, based on this crystal structure, we predicted the crystal habit in vacuum using the attachment energy (AE) method and considered solvent effects in a systematic way using the modified attachment energy (MAE) model. The simulation can accurately construct a complete process from molecule to crystal structure to morphology prediction. Experimentally, we observed crystal morphologies in four different polarity solvents compounds (ethanol, acetonitrile, ethyl acetate, and toluene). We found that the aspect ratio decreases of crystal habits in this ibuprofen system were found to vary with increasing solvent relative polarity. Besides, the modified crystal morphologies are in good agreement with the observed experimental morphologies. Finally, this work may guide computer-aided design of the desirable crystal morphology.
CCDC 1416891: Experimental Crystal Structure Determination : Methyl-triphenyl-germanium
Bernatowicz, Piotr
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1408042: Experimental Crystal Structure Determination : 6,13-dimesitylpentacene
Shi, Xueliang
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Crystal structure of enolase from Drosophila melanogaster.
Sun, Congcong; Xu, Baokui; Liu, Xueyan; Zhang, Zhen; Su, Zhongliang
2017-04-01
Enolase is an important enzyme in glycolysis and various biological processes. Its dysfunction is closely associated with diseases. Here, the enolase from Drosophila melanogaster (DmENO) was purified and crystallized. A crystal of DmENO diffracted to 2.0 Å resolution and belonged to space group R32. The structure was solved by molecular replacement. Like most enolases, DmENO forms a homodimer with conserved residues in the dimer interface. DmENO possesses an open conformation in this structure and contains conserved elements for catalytic activity. This work provides a structural basis for further functional and evolutionary studies of enolase.
Hydrogen-bonded co-crystal structure of benzoic acid and zwitterionic l-proline
Directory of Open Access Journals (Sweden)
Aaron M. Chesna
2017-03-01
Full Text Available The title compound [systematic name: benzoic acid–pyrrolidin-1-ium-2-carboxylate (1/1], C7H6O2·C5H9NO2, is an example of the application of non-centrosymmetric co-crystallization for the growth of a crystal containing a typically centrosymmetric component in a chiral space group. It co-crystallizes in the space group P212121 and contains benzoic acid and l-proline in equal proportions. The crystal structure exhibits chains of l-proline zwitterions capped by benzoic acid molecules which form a C(5[R33(11] hydrogen-bonded network along [100]. The crystal structure is examined and compared to that of a similar co-crystal containing l-proline zwitterions and 4-aminobenzoic acid.
Macromolecular Crystallization in Microfluidics for the International Space Station
Monaco, Lisa A.; Spearing, Scott
2003-01-01
At NASA's Marshall Space Flight Center, the Iterative Biological Crystallization (IBC) project has begun development on scientific hardware for macromolecular crystallization on the International Space Station (ISS). Currently ISS crystallization research is limited to solution recipes that were prepared on the ground prior to launch. The proposed hardware will conduct solution mixing and dispensing on board the ISS, be fully automated, and have imaging functions via remote commanding from the ground. Utilizing microfluidic technology, IBC will allow for on orbit iterations. The microfluidics LabChip(R) devices that have been developed, along with Caliper Technologies, will greatly benefit researchers by allowing for precise fluid handling of nano/pico liter sized volumes. IBC will maximize the amount of science return by utilizing the microfluidic approach and be a valuable tool to structural biologists investigating medically relevant projects.
CCDC 870534: Experimental Crystal Structure Determination : Dichloro-trimethyl-tantalum(v)
Chen, Yin; Callens, E.; Abou-Hamad, E.; Merle, N.; White, A.J.P.; Taoufik, M.; Coperet, C.; Le Roux, E.; Basset, J.-M.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1475931: Experimental Crystal Structure Determination : trimethylammonium trichloro-tin(iv)
Dang, Yangyang
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1475929: Experimental Crystal Structure Determination : trimethylammonium tribromo-tin(iv)
Dang, Yangyang
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1482638: Experimental Crystal Structure Determination : trimethylammonium trichloro-tin(iv)
Dang, Yangyang
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1475930: Experimental Crystal Structure Determination : trimethylammonium trichloro-tin(iv)
Dang, Yangyang
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Economic analysis of crystal growth in space
Ulrich, D. R.; Chung, A. M.; Yan, C. S.; Mccreight, L. R.
1972-01-01
Many advanced electronic technologies and devices for the 1980's are based on sophisticated compound single crystals, i.e. ceramic oxides and compound semiconductors. Space processing of these electronic crystals with maximum perfection, purity, and size is suggested. No ecomonic or technical justification was found for the growth of silicon single crystals for solid state electronic devices in space.
Isolation, crystallization and crystal structure determination of bovine kidney Na(+),K(+)-ATPase.
Gregersen, Jonas Lindholt; Mattle, Daniel; Fedosova, Natalya U; Nissen, Poul; Reinhard, Linda
2016-04-01
Na(+),K(+)-ATPase is responsible for the transport of Na(+) and K(+) across the plasma membrane in animal cells, thereby sustaining vital electrochemical gradients that energize channels and secondary transporters. The crystal structure of Na(+),K(+)-ATPase has previously been elucidated using the enzyme from native sources such as porcine kidney and shark rectal gland. Here, the isolation, crystallization and first structure determination of bovine kidney Na(+),K(+)-ATPase in a high-affinity E2-BeF3(-)-ouabain complex with bound magnesium are described. Crystals belonging to the orthorhombic space group C2221 with one molecule in the asymmetric unit exhibited anisotropic diffraction to a resolution of 3.7 Å with full completeness to a resolution of 4.2 Å. The structure was determined by molecular replacement, revealing unbiased electron-density features for bound BeF3(-), ouabain and Mg(2+) ions.
CCDC 1024814: Experimental Crystal Structure Determination : 1,3-Dimesitylimidazolidine-2-selenone
Vummaleti, Sai V. C.; Nelson, David J.; Poater, Albert; Gó mez-Suá rez, Adriá n; Cordes, David B.; Slawin, Alexandra M. Z.; Nolan, Steven P.; Cavallo, Luigi
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Jiawei
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Jiawei
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Structures of the OmpF porin crystallized in the presence of foscholine-12.
Kefala, Georgia; Ahn, Chihoon; Krupa, Martin; Esquivies, Luis; Maslennikov, Innokentiy; Kwiatkowski, Witek; Choe, Senyon
2010-05-01
The endogenous Escherichia coli porin OmpF was crystallized as an accidental by-product of our efforts to express, purify, and crystallize the E. coli integral membrane protein KdpD in the presence of foscholine-12 (FC12). FC12 is widely used in membrane protein studies, but no crystal structure of a protein that was both purified and crystallized with this detergent has been reported in the Protein Data Bank. Crystallization screening for KdpD yielded two different crystals of contaminating protein OmpF. Here, we report two OmpF structures, the first membrane protein crystal structures for which extraction, purification, and crystallization were done exclusively with FC12. The first structure was refined in space group P21 with cell parameters a = 136.7 A, b = 210.5 A, c = 137 A, and beta = 100.5 degrees , and the resolution of 3.8 A. The second structure was solved at the resolution of 4.4 A and was refined in the P321 space group, with unit cell parameters a = 215.5 A, b = 215.5 A, c = 137.5 A, and gamma = 120 degrees . Both crystal forms show novel crystal packing, in which the building block is a tetrahedral arrangement of four trimers. Additionally, we discuss the use of FC12 for membrane protein crystallization and structure determination, as well as the problem of the OmpF contamination for membrane proteins overexpressed in E. coli.
Mithila, Farha J; Oyola-Reynoso, Stephanie; Thuo, Martin M; Atkinson, Manza Bj
2016-01-01
Structural distortions due to hyperconjugation in organic molecules, like norbornenes, are well captured through X-ray crystallographic data, but are sometimes difficult to visualize especially for those applying chemical knowledge and are not chemists. Crystal structure from the Cambridge database were downloaded and converted to .stl format. The structures were then printed at the desired scale using a 3D printer. Replicas of the crystal structures were accurately reproduced in scale and any resulting distortions were clearly visible from the macroscale models. Through space interactions or effect of through space hyperconjugation was illustrated through loss of symmetry or distortions thereof. The norbornene structures exhibits distortion that cannot be observed through conventional ball and stick modelling kits. We show that 3D printed models derived from crystallographic data capture even subtle distortions in molecules. We translate such crystallographic data into scaled-up models through 3D printing.
Crystal structure and crystal growth of the polar ferrimagnet CaBaFe4O7
Perry, R. S.; Kurebayashi, H.; Gibbs, A.; Gutmann, M. J.
2018-05-01
Magnetic materials are a cornerstone for developing spintronic devices for the transport of information via magnetic excitations. To date, relatively few materials have been investigated for the purpose of spin transport, mostly due to the paucity of suitable candidates as these materials are often chemically complex and difficult to synthesize. We present the crystal growth and a structure solution on the high-temperature crystal structure of the layered, polar ferrimagnet CaBaFe4O7 , which is a possible new contender for spintronics research. The space group is identified as P 3 by refinement of single crystal and powder neutron diffraction data. At 400 K, the trigonal lattice parameters are a =11.0114 (11 )Å and c =10.330 (3 )Å . The structure is similar to the low-temperature phase with alternating layers of triangular and Kagome-arranged Fe-O tetrahedra. We also present details of the crystal growth by traveling solvent method.
CCDC 1048727: Experimental Crystal Structure Determination : bis(2-(hydroxyimino)propanoato)-tin(ii)
Khanderi, Jayaprakash; Davaasuren, Bambar; Alshankiti, Buthainah; Rothenberger, Alexander
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Haque, M.A.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1429311: Experimental Crystal Structure Determination : N-(5-Bromoquinolin-8-yl)benzamide
Xu, Jun; Shen, Chao; Zhu, Xiaolei; Zhang, Pengfei; Ajitha, Manjaly John; Huang, Kuo-Wei; An, Zhongfu; Liu, Xiaogang
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Huang, Yangjie
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Marchewka, M. K.; Pietraszko, A.
2008-02-01
The piperazinium bis(4-hydroxybenzenesulphonate) crystallizes from water solution at room temperature in P2 1/ c space group of monoclinic system. The crystals are built up of doubly protonated piperazinium cations and ionized 4-hydroxybenzenesulphonate anions that interact through weak hydrogen bonds of O-H⋯O and N-H⋯O type. Mutual orientation of anions is determined by non-conventional hydrogen bonds of C-H⋯π type. Room temperature powder FT IR and FT Raman measurements were carried out. The vibrational spectra are in full agreement with the structure obtained from X-ray crystallography. The big single crystals of the title salt can be grown.
Crystal structure of PrRh4.8B2
International Nuclear Information System (INIS)
Higashi, Iwami; Shishido, Toetsu; Takei, Humihiko; Kobayashi, Takaaki
1988-01-01
The crystal structure of a new rare earth ternary boride PrRh 4.8 B 2 was investigated, by single-crystal X-ray diffractometry. PrRh 4.8 B 2 crystallizes in the orthorhombic space group Immm with a = 9.697(4), b = 5.577(2), c = 25.64(3) A, Z=12. The intensity data were collected on a four-circle diffractometer with graphite-monochromatized Mo Kα radiation. The structure was solved by the Patterson method and refined with a full-matrix least-squares program to an R value (equal to Σvertical strokeΔFvertical stroke/Σvertical strokeF 0 vertical stroke) of 0.055 for 1176 reflections. (orig.)
X-ray crystal structure and small-angle X-ray scattering of sheep liver sorbitol dehydrogenase
DEFF Research Database (Denmark)
Yennawar, Hemant; Møller, Magda; Gillilan, Richard
2011-01-01
The X-ray crystal structure of sheep liver sorbitol dehydrogenase (slSDH) has been determined using the crystal structure of human sorbitol dehydrogenase (hSDH) as a molecular-replacement model. slSDH crystallized in space group I222 with one monomer in the asymmetric unit. A conserved tetramer...
Infrared Fibers for Use in Space-Based Smart Structures
Tucker, Dennis S.; Nettles, Alan T.; Brantley, Lott W. (Technical Monitor)
2001-01-01
Infrared optical fibers are finding a number of applications including laser surgery, remote sensing, and nuclear radiation resistant links. Utilizing these fibers in space-based structures is another application, which can be exploited. Acoustic and thermal sensing are two areas in which these fibers could be utilized. In particular, fibers could be embedded in IM7/8552 toughened epoxy and incorporated into space structures both external and internal. ZBLAN optical fibers are a candidate, which have been studied extensively over the past 20 years for terrestrial applications. For the past seven years the effects of gravity on the crystallization behavior of ZBLAN optical fiber has been studied. It has been found that ZBLAN crystallization is suppressed in microgravity. This lack of crystallization leads to a fiber with better transmission characteristics than its terrestrial counterpart.
Crystal structure and magnetism of UOsAl
Energy Technology Data Exchange (ETDEWEB)
Andreev, A.V., E-mail: andreev@fzu.cz [Institute of Physics, Academy of Sciences, Na Slovance 2, 182 21 Prague (Czech Republic); Daniš, S. [Department of Condensed Matter Physics, Charles University, Ke Karlovu 5, 121 16 Prague (Czech Republic); Šebek, J.; Henriques, M.S.; Vejpravová, J. [Institute of Physics, Academy of Sciences, Na Slovance 2, 182 21 Prague (Czech Republic); Gorbunov, D.I. [Institute of Physics, Academy of Sciences, Na Slovance 2, 182 21 Prague (Czech Republic); Dresden High Magnetic Field Laboratory (HLD-EMFL), Helmholtz-Zentrum, Dresden-Rossendorf, D-01314 Dresden (Germany); Havela, L. [Department of Condensed Matter Physics, Charles University, Ke Karlovu 5, 121 16 Prague (Czech Republic)
2017-04-15
Crystal structure, magnetization, and specific heat were studied on single crystal of uranium intermetallic compound UOsAl. It is a hexagonal Laves phase of MgZn{sub 2} type, space group P6{sub 3}/mmc, with lattice parameters a=536.4 pm, c=845.3 pm. Shortest inter-uranium distance 313 pm (along the c-axis) is considerably smaller than the Hill limit (340 pm). The compound is a weakly temperature-dependent paramagnet with magnetic susceptibility of ≈1.5*10{sup −8} m{sup 3} mol{sup −1} (at T=2 K), which is slightly higher with magnetic field along the a-axis compared to the c-axis. The Sommerfeld coefficient of electronic specific heat has moderate value of γ=36 mJ mol{sup −1} K{sup −2}. - Highlights: • Crystal structure and magnetic properties were studied on single crystal of UOsAl with hexagonal structure of MgZn{sub 2} type. • Shortest inter-uranium distance 313 pm (along the c-axis) is considerably smaller than the Hill limit (340 pm). • UOsAl has paramagnetic ground state as the compounds with T=Fe and Ru, i.e. 3d and 4d analogues of Os.
CCDC 963856: Experimental Crystal Structure Determination : catena-[bis(mu2-2-methylimidazole)-zinc
Shekhah, Osama; Swaidan, Raja; Belmabkhout, Youssef; du Plessis, Marike; Jacobs, Tia; Barbour, Leonard J.; Pinnau, Ingo; Eddaoudi, Mohamed
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wu, Melissa M.; Gill, Arran M.; Yunpeng, Lu; Yongxin, Li; Ganguly, Rakesh; Falivene, Laura; Garcí a, Felipe
2017-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wu, Melissa M.; Gill, Arran M.; Yunpeng, Lu; Yongxin, Li; Ganguly, Rakesh; Falivene, Laura; Garcí a, Felipe
2017-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1059905: Experimental Crystal Structure Determination : 7,13-dimesitylindeno[1,2-b]thioxanthene
Shi, Xueliang; Kueh, Weixiang; Zheng, Bin; Huang, Kuo-Wei; Chi, Chunyan
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Al-Masri, H.T.; Emwas, Abdul-Hamid M.; Al-Talla, Zeyad; Al Kordi, Mohamed
2012-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Roesle, Philipp; Caporaso, Lucia; Schnitte, Manuel; Goldbach, Verena; Cavallo, Luigi; Mecking, Stefan
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Reiner, Thomas; Jantke, Dominik; Miao, Xiao-He; Marziale, Alexander N.; Kiefer, Florian J.; Eppinger, Jö rg
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Reiner, T.
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Plonka, Anna M.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Plonka, Anna M.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Plonka, Anna M.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Khanderi, Jayaprakash
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Design considerations for a Space Shuttle Main Engine turbine blade made of single crystal material
Abdul-Aziz, A.; August, R.; Nagpal, V.
1993-01-01
Nonlinear finite-element structural analyses were performed on the first stage high-pressure fuel turbopump blade of the Space Shuttle Main Engine. The analyses examined the structural response and the dynamic characteristics at typical operating conditions. Single crystal material PWA-1480 was considered for the analyses. Structural response and the blade natural frequencies with respect to the crystal orientation were investigated. The analyses were conducted based on typical test stand engine cycle. Influence of combined thermal, aerodynamic, and centrifugal loadings was considered. Results obtained showed that the single crystal secondary orientation effects on the maximum principal stresses are not highly significant.
Shieh, Huey-Sheng; Ghisla, Sandro; Hanson, Louise Karle; Ludwig, Martha L.; Nordman, Christer E.
1981-01-01
The molecular complex lumiflavin-2-aminobenzoic acid monohydrate (C13H12N402●C7H7N02●H2O)crystallizes from aqueous solution as red triclinic prisms. The space group is P1 with cell dimensions a = 9.660 A, b = 14.866 Å, c = 7.045 Å, α = 95.44°, β = 95.86°, and γ = 105.66°. The crystal structure was solved by direct methods and refined by block-diagonal least-squares procedures to an R value of 0.050 on the basis of 1338 observed reflections. The structure is composed of stacks of alternating l...
Directory of Open Access Journals (Sweden)
Gerd Meyer
2010-12-01
Full Text Available The majority of the earth’s crust is made up of crystalline material. The research areas of mineralogy, petrology, chimie minerále (inorganic chemistry and, of course, crystallography outgrew from the fascination of mankind with the color and symmetry of crystals. Crystals have translational symmetry in two or three dimensions, quasicrystals have translational symmetry in higher spaces. Further symmetries may be observed by the eye, by microscopic techniques or by the diffraction of X-ray, electron, or neutron beams. Diffraction techniques are also used, due to Max von Laue’s eminent discovery a century ago, to determine crystal structures. [...
Shekhah, Osama; Swaidan, Raja; Belmabkhout, Youssef; du Plessis, Marike; Jacobs, Tia; Barbour, Leonard J.; Pinnau, Ingo; Eddaoudi, Mohamed
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Shekhah, Osama; Swaidan, Raja; Belmabkhout, Youssef; du Plessis, Marike; Jacobs, Tia; Barbour, Leonard J.; Pinnau, Ingo; Eddaoudi, Mohamed
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Shekhah, Osama; Swaidan, Raja; Belmabkhout, Youssef; du Plessis, Marike; Jacobs, Tia; Barbour, Leonard J.; Pinnau, Ingo; Eddaoudi, Mohamed
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Shekhah, Osama; Swaidan, Raja; Belmabkhout, Youssef; du Plessis, Marike; Jacobs, Tia; Barbour, Leonard J.; Pinnau, Ingo; Eddaoudi, Mohamed
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Kuhn, Paul-Steffen; Cremer, Laura; Gavriluta, Anatolie; Jovanović, Katarina K.; Filipović, Lana; Hummer, Alfred A.; Bü chel, Gabriel E.; Dojčinović, Biljana P.; Meier, Samuel M.; Rompel, Annette; Radulović, Siniša; Tommasino, Jean Bernard; Luneau, Dominique; Arion, Vladimir B.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Al-Masri, H.T.; Emwas, Abdul-Hamid M.; Al-Talla, Zeyad; Al Kordi, Mohamed
2012-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1025419: Experimental Crystal Structure Determination : bisthieno[3,2-b:2',3'-d]thiophene
Castañ eda, Raú l; Khrustalev, Victor N.; Fonari, Alexandr; Bredas, Jean-Luc; Getmanenko, Yulia A.; Timofeeva, Tatiana V.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1015953: Experimental Crystal Structure Determination : 1,3,6,8-tetrakis(4-phenoxyphenyl)pyrene
El-Assaad, Tarek H.; Auer, Manuel; Castañ eda, Raul; Hallal, Kassem M.; Jradi, Fadi M.; Mosca, Lorenzo; Khnayzer, Rony S.; Patra, Digambara; Timofeeva, Tatiana V.; Bredas, Jean-Luc; List-Kratochvil, Emil J. W.; Wex, Brigitte; Kaafarani, Bilal R.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1011330: Experimental Crystal Structure Determination : 1,3,6,8-tetrakis(4-fluorophenyl)pyrene
El-Assaad, Tarek H.; Auer, Manuel; Castañ eda, Raul; Hallal, Kassem M.; Jradi, Fadi M.; Mosca, Lorenzo; Khnayzer, Rony S.; Patra, Digambara; Timofeeva, Tatiana V.; Bredas, Jean-Luc; List-Kratochvil, Emil J. W.; Wex, Brigitte; Kaafarani, Bilal R.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Urbina-Blanco, C.A.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1436717: Experimental Crystal Structure Determination : 2-bromo-4,5-diiodo-1,3-thiazole
Shi, Qinqin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1436716: Experimental Crystal Structure Determination : 5-fluoro-4-iodo-2,1,3-benzothiadiazole
Shi, Qinqin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wang, Xinbo
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Khanderi, Jayaprakash
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Al Kordi, Mohamed
2017-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Weng, Zhiqiang
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Huang, Yangjie
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Re-investigation of the crystal structure of enstatite under high-pressure conditions
DEFF Research Database (Denmark)
Periotto, Benedetta; Balic Zunic, Tonci; Nestola, Fabrizio
2012-01-01
A synthetic single crystal of pure orthoenstatite (MgSiO3, space group Pbca) has been investigated at high pressure for structural determinations by in situ single-crystal X‑ray diffraction using a diamond-anvil cell. Ten complete intensity data collections were performed up to 9.36 GPa. This study...... with different compositions. The structural evolution determined in this work confirms the high-pressure evolution found previously for other orthopyroxenes and removes some ambiguities originating from the less accurate published data on the MgSiO3 structure at high pressure. The structural compression...
Shear induced structures in crystallizing cocoa butter
Mazzanti, Gianfranco; Guthrie, Sarah E.; Sirota, Eric B.; Marangoni, Alejandro G.; Idziak, Stefan H. J.
2004-03-01
Cocoa butter is the main structural component of chocolate and many cosmetics. It crystallizes in several polymorphs, called phases I to VI. We used Synchrotron X-ray diffraction to study the effect of shear on its crystallization. A previously unreported phase (phase X) was found and a crystallization path through phase IV under shear was observed. Samples were crystallized under shear from the melt in temperature controlled Couette cells, at final crystallization temperatures of 17.5^oC, 20^oC and 22.5^oC in Beamline X10A of NSLS. The formation of phase X was observed at low shear rates (90 s-1) and low crystallization temperature (17.5^oC), but was absent at high shear (720 s-1) and high temperature (20^oC). The d-spacing and melting point suggest that this new phase is a mixture rich on two of the three major components of cocoa butter. We also found that, contrary to previous reports, the transition from phase II to phase V can happen through the intermediate phase IV, at high shear rates and temperature.
An arc detector for neutron crystal structure investigations
Energy Technology Data Exchange (ETDEWEB)
Habib, N [Reactor and Neutron Physics Dept., Nuclear Research Center. AEA, Cairo (Egypt)
1997-12-31
An arc detector for neutron structure investigations of powder crystals using time-of-flight technique is described. In order to enable the measurement of integral intensity from about 1/4 of the Debye-Scherrer ring and for simplicity reasons, the scattering angle 20-90 degree was chosen and a special arc collimator was built. The arc collimator-detector had a divergency of about 20 minutes of arc, and the distance between detector-sample was 64 cm. Four {sup 3} He detectors were fixed on the arc of the collimator. Both efficiency and space sensitivity of the detector were determined using a point neutron source. Results of measurements show that parameters of the arc detector are acceptable for high resolution crystal structure investigations. 6 figs.
The Ag2Se-HgSe-GeSe2 system and crystal structures of the compounds
International Nuclear Information System (INIS)
Parasyuk, O.V.; Gulay, L.D.; Romanyuk, Ya.E.; Olekseyuk, I.D.; Piskach, L.V.
2003-01-01
The phase diagram of the quasi-ternary Ag 2 Se-HgSe-GeSe 2 system at 298 K was investigated using X-ray phase analysis and metallography. The formation of five intermediate quaternary phases β (Ag ∼7.12-∼6.32 Hg ∼0.44-∼0.82 GeSe 6 ), γ (Ag ∼6.08-∼4.00 Hg ∼0.96-∼2.00 GeSe 6 ), δ (Ag 3.4 Hg 2.3 GeSe 6 ), ε (Ag ∼2.24-∼2.00 Hg ∼2.88-∼3.00 GeSe 6 ) and ∼Ag 1.4 Hg 1.3 GeSe 6 was established. The crystal structure of the β-phase (for the Ag 6.504 Hg 0.912 GeSe 6 composition) was determined using X-ray single crystal diffraction. It crystallizes in a cubic structure (space group F4-bar 3m) with the lattice parameter a=1.09026(4) nm. The crystal structure of the δ-phase (Ag 3.4 Hg 2.3 GeSe 6 ) was determined using X-ray powder diffraction (space group F4-bar 3m, a=1.07767(8) nm). The crystal structure determination of the γ-phase (space group Pmn2 1 ) was performed for the compositions Ag 5.6 Hg 1.2 GeSe 6 , Ag 4.8 Hg 1.6 GeSe 6 and Ag 4 Hg 2 GeSe 6 using X-ray powder diffraction. The crystal structure of the LT-Hg 2 GeSe 4 compound (space group I4-bar , a=0.56786(2), c=1.12579(5) nm) was confirmed by powder diffraction also.
X-ray crystal structure and small-angle X-ray scattering of sheep liver sorbitol dehydrogenase
Energy Technology Data Exchange (ETDEWEB)
Yennawar, Hemant [Pennsylvania State University, 8 Althouse Laboratory, University Park, PA 16802 (United States); Møller, Magda [Cornell High Energy Synchrotron Source, Ithaca, NY 14853 (United States); University of Copenhagen, DK-2100 Copenhagen (Denmark); Gillilan, Richard [Cornell High Energy Synchrotron Source, Ithaca, NY 14853 (United States); Yennawar, Neela, E-mail: nhy1@psu.edu [Pennsylvania State University, 8 Althouse Laboratory, University Park, PA 16802 (United States)
2011-05-01
The X-ray crystal structure and a small-angle X-ray scattering solution structure of sheep liver sorbitol dehydrogenase have been determined. The details of the interactions that enable the tetramer scaffold to be the functional biological unit have been analyzed. The X-ray crystal structure of sheep liver sorbitol dehydrogenase (slSDH) has been determined using the crystal structure of human sorbitol dehydrogenase (hSDH) as a molecular-replacement model. slSDH crystallized in space group I222 with one monomer in the asymmetric unit. A conserved tetramer that superposes well with that seen in hSDH (despite belonging to a different space group) and obeying the 222 crystal symmetry is seen in slSDH. An acetate molecule is bound in the active site, coordinating to the active-site zinc through a water molecule. Glycerol, a substrate of slSDH, also occupies the substrate-binding pocket together with the acetate designed by nature to fit large polyol substrates. The substrate-binding pocket is seen to be in close proximity to the tetramer interface, which explains the need for the structural integrity of the tetramer for enzyme activity. Small-angle X-ray scattering was also used to identify the quaternary structure of the tetramer of slSDH in solution.
The Synthesis and Crystal Structure of Two New Hydrazone Compounds
Directory of Open Access Journals (Sweden)
Li-Hua Wang
2016-05-01
Full Text Available Two new hydrazone compounds, 4-formylimidazole-4-hydroxybenzhydrazone dihydrate (1 and 2-nitrobenzaldehyde-2-furan formylhydrazone (2, were synthesized via the classical synthesis method. Their structure was determined via elemental analysis and X-ray single crystal diffraction analysis. Compound 1 crystallizes in triclinic, space group P-1 with a = 7.0321(14 Å, b = 7.3723(15 Å, c = 13.008(3 Å, α = 98.66(3°, β = 101.69(3°, γ = 92.25(3°, V = 651.2(2 Å3, Z = 2, Dc = 1.358 g·cm−3, μ = 0.106 mm−1, F(000 = 280, and final R1 = 0.0564, wR2 = 0.1420. Compound 2 crystallizes in monoclinic, space group P21/c with a = 17.3618(9 Å, b = 9.1506(4 Å, c = 15.5801(7 Å, β = 104.532(5°, V = 2396.05(19 Å3, Z = 8, Dc = 1.437 g·cm−3, μ = 0.111 mm−1, F(000 = 1072, and final R1 = 0.0633, wR2 = 0.1649. Compound 1 forms a 2D-layered structure via the interactions of 1D chains and Compound 2 forms a 3D network structure via the interactions of 1D chains.
Path-integral and Ornstein-Zernike study of quantum fluid structures on the crystallization line
International Nuclear Information System (INIS)
Sesé, Luis M.
2016-01-01
Liquid neon, liquid para-hydrogen, and the quantum hard-sphere fluid are studied with path integral Monte Carlo simulations and the Ornstein-Zernike pair equation on their respective crystallization lines. The results cover the whole sets of structures in the r-space and the k-space and, for completeness, the internal energies, pressures and isothermal compressibilities. Comparison with experiment is made wherever possible, and the possibilities of establishing k-space criteria for quantum crystallization based on the path-integral centroids are discussed. In this regard, the results show that the centroid structure factor contains two significant parameters related to its main peak features (amplitude and shape) that can be useful to characterize freezing.
Path-integral and Ornstein-Zernike study of quantum fluid structures on the crystallization line
Energy Technology Data Exchange (ETDEWEB)
Sesé, Luis M., E-mail: msese@ccia.uned.es [Departamento de Ciencias y Técnicas Fisicoquímicas, Universidad Nacional de Educación a Distancia, Paseo Senda del Rey 9, 28040 Madrid (Spain)
2016-03-07
Liquid neon, liquid para-hydrogen, and the quantum hard-sphere fluid are studied with path integral Monte Carlo simulations and the Ornstein-Zernike pair equation on their respective crystallization lines. The results cover the whole sets of structures in the r-space and the k-space and, for completeness, the internal energies, pressures and isothermal compressibilities. Comparison with experiment is made wherever possible, and the possibilities of establishing k-space criteria for quantum crystallization based on the path-integral centroids are discussed. In this regard, the results show that the centroid structure factor contains two significant parameters related to its main peak features (amplitude and shape) that can be useful to characterize freezing.
Time Crystal Platform: From Quasicrystal Structures in Time to Systems with Exotic Interactions
Giergiel, Krzysztof; Miroszewski, Artur; Sacha, Krzysztof
2018-04-01
Time crystals are quantum many-body systems that, due to interactions between particles, are able to spontaneously self-organize their motion in a periodic way in time by analogy with the formation of crystalline structures in space in condensed matter physics. In solid state physics properties of space crystals are often investigated with the help of external potentials that are spatially periodic and reflect various crystalline structures. A similar approach can be applied for time crystals, as periodically driven systems constitute counterparts of spatially periodic systems, but in the time domain. Here we show that condensed matter problems ranging from single particles in potentials of quasicrystal structure to many-body systems with exotic long-range interactions can be realized in the time domain with an appropriate periodic driving. Moreover, it is possible to create molecules where atoms are bound together due to destructive interference if the atomic scattering length is modulated in time.
Synthesis and Crystal Structure of 1-Chloro-2-methyl-4-nitrobenzene
Directory of Open Access Journals (Sweden)
Jim Simpson
2012-03-01
Full Text Available The title compound (3 was prepared from 4-chloroaniline in good yield on successive oxidation and methylation and its crystal and molecular structure is reported. The compound crystallizes in the monoclinic space group P 21/n with unit cell dimensions a = 13.5698(8, b = 3.7195 (3, c = 13.5967 (8 Å, ß = 91.703(3 °, V = 685.96 (10 Å3. The molecule is essentially planar with a dihedral angle of 6.2(3 ° between the nitro group and the phenyl ring. The crystal structure is stabilised by π...π contacts between adjacent benzene rings together with C–H...O hydrogen bonds and close Cl...O contacts.
Simulation and design of the photonic crystal microwave accelerating structure
International Nuclear Information System (INIS)
Song Ruiying; Wu Congfeng; He Xiaodong; Dong Sai
2007-01-01
The authors have derived the global band gaps for general two-dimensional (2D) photonic crystal microwave accelerating structures formed by square or triangular arrays of metal posts. A coordinate-space, finite-difference code was used to calculate the complete dispersion curves for the lattices. The fundamental and higher frequency global photonic band gaps were determined numerically. The structure formed by triangular arrays of metal posts with a missing rod at the center has advantages of higher-order-modes (HOM) suppression and main mode restriction under the condition of a/b<0.2. The relationship between the RF properties and the geometrical parameters have been studied for the 9.37 GHz photonic crystal accelerating structure. The Rs, Q, Rs/Q of the new structure may be comparable to the disk-loaded accelerating structure. (authors)
Abulikemu, Mutalifu; Ould-Chikh, Samy; Miao, Xiaohe; Alarousu, Erkki; Banavoth, Murali; Ngongang Ndjawa, Guy Olivier; Barbe, Jeremy; El Labban, Abdulrahman; Amassian, Aram; Del Gobbo, Silvano
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Shekhah, Osama; Swaidan, Raja; Belmabkhout, Youssef; du Plessis, Marike; Jacobs, Tia; Barbour, Leonard J.; Pinnau, Ingo; Eddaoudi, Mohamed
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Kuhn, Paul-Steffen; Bü chel, Gabriel E.; Jovanović, Katarina K.; Filipović, Lana; Radulović, Siniša; Rapta, Peter; Arion, Vladimir B.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Kuhn, Paul-Steffen; Bü chel, Gabriel E.; Jovanović, Katarina K.; Filipović, Lana; Radulović, Siniša; Rapta, Peter; Arion, Vladimir B.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Xu, Jun; Shen, Chao; Zhu, Xiaolei; Zhang, Pengfei; Ajitha, Manjaly John; Huang, Kuo-Wei; An, Zhongfu; Liu, Xiaogang
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1044326: Experimental Crystal Structure Determination : 1,3,6,8-tetrakis(4-t-butylphenyl)pyrene
El-Assaad, Tarek H.; Auer, Manuel; Castañ eda, Raul; Hallal, Kassem M.; Jradi, Fadi M.; Mosca, Lorenzo; Khnayzer, Rony S.; Patra, Digambara; Timofeeva, Tatiana V.; Bredas, Jean-Luc; List-Kratochvil, Emil J. W.; Wex, Brigitte; Kaafarani, Bilal R.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Reiner, T.; Waibel, M.; Marziale, Alexander N.; Jantke, Dominik; Kiefer, F.J.; Fassler, T.F.; Eppinger, Jö rg
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
El-Assaad, Tarek H.; Auer, Manuel; Castañ eda, Raul; Hallal, Kassem M.; Jradi, Fadi M.; Mosca, Lorenzo; Khnayzer, Rony S.; Patra, Digambara; Timofeeva, Tatiana V.; Bredas, Jean-Luc; List-Kratochvil, Emil J. W.; Wex, Brigitte; Kaafarani, Bilal R.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Reiner, Thomas; Jantke, Dominik; Miao, Xiao-He; Marziale, Alexander N.; Kiefer, Florian J.; Eppinger, Jö rg
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Nielsen, Christian B.; White, Andrew J. P.; McCulloch, Iain
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Lakshminarayana, Arun Naibi; Chang, Jingjing; Luo, Jie; Zheng, Bin; Huang, Kuo-Wei; Chi, Chunyan
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Luo, Feng
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CRYSTAL AND MOLECULAR STRUCTURE OF 5-NITROPIRIDINE PIPERIDINE-SULFENAMIDE
Brito, Iván; León, Yasna; Arias, Mauricio; Vargas, Danitza; Carmona, Francisco; Ramírez, Eduardo; Restovic, Ambrosio; Cárdenas, Alejandro; Wittke, Oscar; López-Rodríguez, Matías
2002-01-01
The crystal and molecular structure of 5-nitropiridine piperidine-sulfenamide, C10H13N3O2 S is described and compared with other sulfenamides and with other similar compounds. This structure belongs to a type of divalent sulphur compound and crystallizes in the orthorhombic space group Pnma with a= 27.810(4), b=6.797(1), c=6.110(1)Å, and Dx =1.376 g cm-3 with Z=4. The S-N bond distance of 1.699(4) Å is shorter than a single S-N bond [1.74 Å]. The NO2-(C6H3N)-S-N(C 5H10) molecule lies on a cry...
Rajkumar, M.; Chandramohan, A.
2017-12-01
An organic salt, N,N-diethylanilinium 3,5-dinitrosalicylate was synthesized and single crystals grown by employing the slow solvent evaporation solution growth technique in methanol-acetone (1:1) mixture. The electronic transitions of the salt crystal were studied by UV-Visible spectrum. The optical transmittance window and lower wavelength cut-off of grown crystal have been identified by UV-Vis-NIR studies. The FT-IR spectrum was recorded to confirm the presence of various functional groups in the grown crystal. 1H and 13C NMR spectrum were recorded to establish the molecular structure of the title crystal. Single crystal X-ray diffraction data indicated that the crystal belongs to monoclinic crystal system with P21/n space group. The thermal stability of the crystal was established by TG/DTA studies. The mechanical properties of the grown crystal were studied by Vickers' microhardness technique. The dielectric studies indicated that the dielectric constant and dielectric loss decrease exponentially with frequency at different temperatures.
Transmission electron microscopy: direct observation of crystal structure in refractory ceramics.
Shaw, T M; Thomas, G
1978-11-10
Using high-resolution multibeam interference techniques in the transmission electron microscope, images have been obtained that make possible a real-space structure analysis of a beryllium-silicon-nitrogen compound. The results illustrate the usefulness of lattice imaging in the analysis of local crystal structure in these technologically promising ceramic materials.
Barbosa, Luiz Cláudio de Almeida; Teixeira, Robson Ricardo; Nogueira, Leonardo Brandão; Maltha, Celia Regina Alvares; Doriguetto, Antônio Carlos; Martins, Felipe Terra
2016-02-01
Herein we described structural insights of a series of analogues to helminthosporin phytotoxins. The key reaction used to prepare the compounds corresponded to the [3 + 4] cycloaddition between the oxyallyl cation generated from 2,4-dibromopentan-3-one and different furans. Their structures were confirmed upon IR, NMR and X-ray diffraction analyses. While bicycles 7, 8 and 9 crystallize in the centrosymmetric monoclinic space group P21/c, compound 10 was solved in the noncentrosymmetric orthorhombic space group P212121. The solid materials obtained were shown to be racemic crystals (7, 8, 9) or racemic conglomerate (10). In all compounds, there is formation of a bicycle featured by fused tetrahydropyranone and 2,5-dihydrofuran rings. They adopt chair and envelope conformations, respectively. Crystal packing of all compounds is stabilized through C-H•••O contacts. Conformational aspects as well as similarities and differences among the crystal structures of the synthesized analogues are discussed.
Crystal Structure of Tetragonal Form of La2NiO4+x
Kajitani, Tsuyoshi; Hosoya, Syoichi; Hirabayashi, Makoto; Fukuda, Tsuguo; Onozuka, Takashi
1989-10-01
The crystal structure of the title oxide was studied by means of the X-ray and neutron single crystal diffraction measurements. At room temperature, the tetragonal crystal structure is P42/ncm-type (No. 138), which is one of the subgroup of the space group I4/mmm. The lattice parameters of a sample annealed and slowly cooled in oxygen atmosphere from 673 K are a{=}b{=}5.4640(1) Å and c{=}12.6719(2) Å, while the oxygen content, x{=}0.10(4), was determined from obtained neutron data. The title oxide undergoes a tetragonal (P42/ncm)/tetragonal (I4/mmm) phase transition at about 560 K. The transition temperature is almost identical both in the annealed and as-grown crystals.
Structural coloration of chitosan-cationized cotton fabric using photonic crystals
Yavuz, G.; Zille, A.; Seventekin, N.; Souto, A. P.
2017-10-01
In this work, poly (styrene-methyl methacrylate-acrylic acid) P(St-MMA-AA) composite nanospheres were deposited onto chitosan-cationized woven cotton fabrics followed by a second layer of chitosan. The deposited photonic crystals (PCs) on the fabrics were evaluated for coating efficiency and resistance, chemical analysis and color variation by optical and SEM microscopy, ATR-FTIR, diffuse reflectance spectroscopy and washing fastness. Chitosan deposition on cotton fabric provided cationic groups on the fiber surface promoting electrostatic interaction with photonic crystals. SEM images of the washed samples indicate that the PCs are firmly coated on the cotton surface only in the chitosan treated sample. The photonic nanospheres show an average diameter of 280 nm and display a face-centered cubic closepacking structure with an average thickness of 10 μm. A further chitosan post-treatment enhances color yield of the samples due to the chitosan transparent covering layer that induce bright reflections where the angles of incidence and reflection are the same. After washing, no photonic crystal can be detected on control fabric surface. However, the sample that received a chitosan post-treatment showed a good washing fastness maintaining a reasonable degree of iridescence. Chitosan fills the spaces between the polymer spheres in the matrix stabilizing the photonic structure. Sizeable variations in lattice spacing will allow color variations using more flexible non-close-packed photonic crystal arrays in chitosan hydrogels matrices.
Synthesis, Crystal Structure, and DFT Calculations of 1,3-Diisobutyl Thiourea
Directory of Open Access Journals (Sweden)
Ataf A. Altaf
2015-01-01
Full Text Available 1,3-Diisobutyl thiourea was synthesized and characterized by single crystal X-ray diffraction. It gives a monoclinic (α = γ = 90 and β ≠ 90 structure with the space group P21/c. The unit cell dimensions are a = 11.5131 (4 Å, b = 9.2355 (3 Å, c = 11.3093 (5 Å, α = 90°, β = 99.569° (2, γ = 90°, V = 1185.78 (8 Å3, and Z = 4. The crystal packing is stabilized by intermolecular (N–H⋯S hydrogen bonding in the molecules. The optimized geometry and Mullikan's charges of the said molecule calculated with the help of DFT using B3LYP-6-311G model support the crystal structure.
Hempler, Daniela; Schmidt, Martin U; van de Streek, Jacco
2017-08-01
More than 600 molecular crystal structures with correct, incorrect and uncertain space-group symmetry were energy-minimized with dispersion-corrected density functional theory (DFT-D, PBE-D3). For the purpose of determining the correct space-group symmetry the required tolerance on the atomic coordinates of all non-H atoms is established to be 0.2 Å. For 98.5% of 200 molecular crystal structures published with missed symmetry, the correct space group is identified; there are no false positives. Very small, very symmetrical molecules can end up in artificially high space groups upon energy minimization, although this is easily detected through visual inspection. If the space group of a crystal structure determined from powder diffraction data is ambiguous, energy minimization with DFT-D provides a fast and reliable method to select the correct space group.
Crystals structure of Na3Li(TiF6)2
International Nuclear Information System (INIS)
Popov, D.Yu.; Antokhina, T.F.; Gerasimenko, A.V.; Kajdalova, T.A.; Sergienko, V.I.
2004-01-01
Crystals of Na 3 Li(TiF 6 ) 2 (1) were synthesized in aqueous solution and characterized by the elementary and X-ray phase analysis methods. According to X-ray diffraction analysis data compound 1 is crystallized in a tetragonal crystal system with the following parameters: a=5.130(1), c=18.046(4) A, Z=2, space group P4-bar2 1 c. Alternating layers on the basis of dimers made up by octahedrons of TiF 6 and Na(1)F 6 constitute the frame of compound 1 crystal structure. The dimer layers are joined in a continuous frame by Na(2) and Li cations. Coordination polyhedron of Li atom is tetrahedron (Li-F 1.898(3) A) [ru
Deep Space Detection of Oriented Ice Crystals
Marshak, A.; Varnai, T.; Kostinski, A. B.
2017-12-01
The deep space climate observatory (DSCOVR) spacecraft resides at the first Lagrangian point about one million miles from Earth. A polychromatic imaging camera onboard delivers nearly hourly observations of the entire sun-lit face of the Earth. Many images contain unexpected bright flashes of light over both ocean and land. We constructed a yearlong time series of flash latitudes, scattering angles and oxygen absorption to demonstrate conclusively that the flashes over land are specular reflections off tiny ice crystals floating in the air nearly horizontally. Such deep space detection of tropospheric ice can be used to constrain the likelihood of oriented crystals and their contribution to Earth albedo.
Production, purification, crystallization and structure determination of H-1 Parvovirus
International Nuclear Information System (INIS)
Halder, Sujata; Nam, Hyun-Joo; Govindasamy, Lakshmanan; Vogel, Michèle; Dinsart, Christiane; Salomé, Nathalie; McKenna, Robert; Agbandje-McKenna, Mavis
2012-01-01
The production, purification, crystallization and crystallographic analysis of H-1 Parvovirus, a gene-therapy vector, are reported. Crystals of H-1 Parvovirus (H-1PV), an antitumor gene-delivery vector, were obtained for DNA-containing capsids and diffracted X-rays to 2.7 Å resolution using synchrotron radiation. The crystals belonged to the monoclinic space group P2 1 , with unit-cell parameters a = 255.4, b = 350.4, c = 271.6 Å, β = 90.34°. The unit cell contained two capsids, with one capsid per crystallographic asymmetric unit. The H-1PV structure has been determined by molecular replacement and is currently being refined
Prediction of molecular crystal structures
International Nuclear Information System (INIS)
Beyer, Theresa
2001-01-01
The ab initio prediction of molecular crystal structures is a scientific challenge. Reliability of first-principle prediction calculations would show a fundamental understanding of crystallisation. Crystal structure prediction is also of considerable practical importance as different crystalline arrangements of the same molecule in the solid state (polymorphs)are likely to have different physical properties. A method of crystal structure prediction based on lattice energy minimisation has been developed in this work. The choice of the intermolecular potential and of the molecular model is crucial for the results of such studies and both of these criteria have been investigated. An empirical atom-atom repulsion-dispersion potential for carboxylic acids has been derived and applied in a crystal structure prediction study of formic, benzoic and the polymorphic system of tetrolic acid. As many experimental crystal structure determinations at different temperatures are available for the polymorphic system of paracetamol (acetaminophen), the influence of the variations of the molecular model on the crystal structure lattice energy minima, has also been studied. The general problem of prediction methods based on the assumption that the experimental thermodynamically stable polymorph corresponds to the global lattice energy minimum, is that more hypothetical low lattice energy structures are found within a few kJ mol -1 of the global minimum than are likely to be experimentally observed polymorphs. This is illustrated by the results for molecule I, 3-oxabicyclo(3.2.0)hepta-1,4-diene, studied for the first international blindtest for small organic crystal structures organised by the Cambridge Crystallographic Data Centre (CCDC) in May 1999. To reduce the number of predicted polymorphs, additional factors to thermodynamic criteria have to be considered. Therefore the elastic constants and vapour growth morphologies have been calculated for the lowest lattice energy
Prediction of molecular crystal structures
Energy Technology Data Exchange (ETDEWEB)
Beyer, Theresa
2001-07-01
The ab initio prediction of molecular crystal structures is a scientific challenge. Reliability of first-principle prediction calculations would show a fundamental understanding of crystallisation. Crystal structure prediction is also of considerable practical importance as different crystalline arrangements of the same molecule in the solid state (polymorphs)are likely to have different physical properties. A method of crystal structure prediction based on lattice energy minimisation has been developed in this work. The choice of the intermolecular potential and of the molecular model is crucial for the results of such studies and both of these criteria have been investigated. An empirical atom-atom repulsion-dispersion potential for carboxylic acids has been derived and applied in a crystal structure prediction study of formic, benzoic and the polymorphic system of tetrolic acid. As many experimental crystal structure determinations at different temperatures are available for the polymorphic system of paracetamol (acetaminophen), the influence of the variations of the molecular model on the crystal structure lattice energy minima, has also been studied. The general problem of prediction methods based on the assumption that the experimental thermodynamically stable polymorph corresponds to the global lattice energy minimum, is that more hypothetical low lattice energy structures are found within a few kJ mol{sup -1} of the global minimum than are likely to be experimentally observed polymorphs. This is illustrated by the results for molecule I, 3-oxabicyclo(3.2.0)hepta-1,4-diene, studied for the first international blindtest for small organic crystal structures organised by the Cambridge Crystallographic Data Centre (CCDC) in May 1999. To reduce the number of predicted polymorphs, additional factors to thermodynamic criteria have to be considered. Therefore the elastic constants and vapour growth morphologies have been calculated for the lowest lattice energy
Pump, Eva
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jian, Zhongbao
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jia, Wei-Guo
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Hu, Pan; Lee, Sangsu; Park, Kyu Hyung; Das, Soumyajit; Herng, Tun Seng; Goncalves, Theo; Huang, Kuo-Wei; Ding, Jun; Kim, Dongho; Wu, Jishan
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Hu, Pan; Lee, Sangsu; Seng, Herng Tun; Aratani, Naoki; Zheng, Bin; Yamada, Hiroko; Huang, Kuo-Wei; Ding, Jun; Kim, Dongho; Wu, Jishan
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Weng, Zhiqiang
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
El-Assaad, Tarek H.; Auer, Manuel; Castañ eda, Raul; Hallal, Kassem M.; Jradi, Fadi M.; Mosca, Lorenzo; Khnayzer, Rony S.; Patra, Digambara; Timofeeva, Tatiana V.; Bredas, Jean-Luc; List-Kratochvil, Emil J. W.; Wex, Brigitte; Kaafarani, Bilal R.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Neuwald, B.; Falivene, L.; Caporaso, L.; Cavallo, Luigi; Mecking, S.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Zhijie
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Roesle, P.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zhang, Yan
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Weng, Zhiqiang
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Hayashi, Yukiko
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Weng, Zhiqiang
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Roesle, Philipp; Caporaso, Lucia; Schnitte, Manuel; Goldbach, Verena; Cavallo, Luigi; Mecking, Stefan
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Shekhah, Osama
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Weng, Zhiqiang
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Lu, Hai-Sheng
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Shi, Xueliang
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Eubank, Jarrod F.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Eubank, Jarrod F.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Eubank, Jarrod F.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Luo, Feng
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Directory of Open Access Journals (Sweden)
Dilovan S. Cati
2017-05-01
Full Text Available The complete molecules of the title compounds, N2,N5-bis(pyridin-2-ylmethylpyrazine-2,5-dicarboxamide, C18H16N6O2 (I, 3,6-dimethyl-N2,N5-bis(pyridin-2-ylmethylpyrazine-2,5-dicarboxamide, C20H20N6O2 (II, and N2,N5-bis(pyridin-4-ylmethylpyrazine-2,5-dicarboxamide, C18H16N6O2 (III, are generated by inversion symmetry, with the pyrazine rings being located about centres of inversion. Each molecule has an extended conformation with the pyridine rings inclined to the pyrazine ring by 89.17 (7° in (I, 75.83 (8° in (II and by 82.71 (6° in (III. In the crystal of (I, molecules are linked by N—H...N hydrogen bonds, forming layers lying parallel to the bc plane. The layers are linked by C—H...O hydrogen bonds, forming a three-dimensional supramolecular structure. In the crystal of (II, molecules are also linked by N—H...N hydrogen bonds, forming layers lying parallel to the (10-1 plane. As in (I, the layers are linked by C—H...O hydrogen bonds, forming a three-dimensional supramolecular structure. In the crystal of (III, molecules are again linked by N—H...N hydrogen bonds, but here form corrugated sheets lying parallel to the bc plane. Within the sheets, neighbouring pyridine rings are linked by offset π–π interactions [intercentroid distance = 3.739 (1 Å]. The sheets are linked by C—H...O hydrogen bonds, forming a three-dimensional supramolecular structure. Compound (I crystallizes in the monoclinic space group P21/c. Another monoclinic polymorph, space group C2/c, has been reported on by Cockriel et al. [Inorg. Chem. Commun. (2008, 11, 1–4]. The molecular structures of the two polymorphs are compared.
International Nuclear Information System (INIS)
Li Zhiyuan; Ho Kaiming
2003-01-01
The plane-wave-based transfer-matrix method (TMM) exhibits a peculiar advantage of being capable of solving eigenmodes involved in an infinite photonic crystal and electromagnetic (EM) wave propagation in finite photonic crystal slabs or even semi-infinite photonic crystal structures within the same theoretical framework. In addition, this theoretical approach can achieve much improved numerical convergency in solution of photonic band structures than the conventional plane-wave expansion method. In this paper we employ this TMM in combination with a supercell technique to handle two important kinds of three-dimensional (3D) photonic crystal waveguide structures. The first one is waveguides created in a 3D layer-by-layer photonic crystal that possesses a complete band gap, the other more popular one is waveguides built in a two-dimensional photonic crystal slab. These waveguides usually have mirror-reflection symmetries in one or two directions perpendicular to their axis. We have taken advantage of these structural symmetries to reduce the numerical burden of the TMM solution of the guided modes. The solution to the EM problems under these mirror-reflection symmetries in both the real space and the plane-wave space is discussed in a systematic way and in great detail. Both the periodic boundary condition and the absorbing boundary condition are employed to investigate structures with or without complete 3D optical confinement. The fact that the EM field components investigated in the TMM are collinear with the symmetric axes of the waveguide brings great convenience and clarity in exploring the eigenmode symmetry in both the real space and the plane-wave space. The classification of symmetry involved in the guided modes can help people to better understand the coupling of the photonic crystal waveguides with external channels such as dielectric slab or wire waveguides
International Nuclear Information System (INIS)
Montney, Matthew R.; Supkowski, Ronald M.; Staples, Richard J.; LaDuca, Robert L.
2009-01-01
Hydrothermal reaction of divalent metal chlorides with glutaric acid and 4,4'-dipyridylamine (dpa) has afforded an isostructural family of coordination polymers with formulation [M(glu)(dpa)] n (M=Co (1), Ni (2), Cu (3); glu=glutarate). Square pyramidal coordination is seen in 1-3, with semi-ligation of a sixth donor to produce a '5+1' extended coordination sphere. Neighboring metal atoms are linked into 1D [M(glu)] n neutral chains through chelating/monodentate bridging glutarate moieties with a syn-anti binding mode, and semi-chelation of the pendant carboxylate oxygen. These chains further connect into 2D layers through dipodal dpa ligands. Neighboring layers stack into the pseudo 3D crystal structure of 1-3 through supramolecular hydrogen bonding between dpa amine units and the semi-chelated glutarate oxygen atoms. The variable temperature magnetic behavior of 1-3 was explored and modeled as infinite 1D Heisenberg chains. Notably, complex 3 undergoes a thermally induced single crystal-to-single crystal transformation between centric and acentric space groups, with a conformationally disordered unilayer structure at 293 K and an ordered bilayer structure at 173 K. All materials were further characterized via infrared spectroscopy and elemental and thermogravimetric analyses. - Graphical abstract: The coordination polymers [M(glu)(dpa)] n (M=Co (1), Ni (2), Cu (3); glu=glutarate, dpa=4,4'-dipyridylamine) exhibit 2D layer structures based on 1D [M(glu)] n chains linked through dpa tethers. Antiferromagnetic coupling is observed for 2 and 3, while ferromagnetism is predominant in 1. Compound 3 undergoes a thermally induced single crystal-to-single crystal transformation from an acentric to a centrosymmetric space group
Structural study of quasi-one-dimensional vanadium pyroxene LiVSi{sub 2}O{sub 6} single crystals
Energy Technology Data Exchange (ETDEWEB)
Ishii, Yuto [Department of Physics, Hokkaido University, Sapporo 060-0810 (Japan); Matsushita, Yoshitaka [National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Oda, Migaku; Yoshida, Hiroyuki [Department of Physics, Hokkaido University, Sapporo 060-0810 (Japan)
2017-02-15
Single crystals of quasi-one-dimensional vanadium pyroxene LiVSi{sub 2}O{sub 6} were synthesized and the crystal structures at 293 K and 113 K were studied using X-ray diffraction experiments. We found a structural phase transition from the room-temperature crystal structure with space group C2/c to a low-temperature structure with space group P2{sub 1}/c, resulting from a rotational displacement of SiO{sub 4} tetrahedra. The temperature dependence of magnetic susceptibility shows a broad maximum around 116 K, suggesting an opening of the Haldane gap expected for one-dimensional antiferromagnets with S=1. However, an antiferromagnetic long-range order was developed below 24 K, probably caused by a weak inter-chain magnetic coupling in the compound. - Graphical abstract: Low temperature crystal structure of LiVSi{sub 2}O{sub 6} and an orbital arrangement within the V-O zig-zag chain along the c-axis. - Highlights: • A low temperature structure of LiVSi{sub 2}O{sub 6} was determined by single crystal X-ray diffraction measurements. • The origin of the structural transition is a rotational displacement of SiO{sub 4} tetrahedra. • The uniform orbital overlap in the V-O zigzag chain makes the system a quasi one-dimensional antiferromagnet.
Crystal structure and phase transitions in perovskite-like C(NH2)3SnCl3
International Nuclear Information System (INIS)
Szafranski, Marek; Stahl, Kenny
2007-01-01
X-ray single-crystal diffraction, high-temperature powder diffraction and differential thermal analysis at ambient and high pressure have been employed to study the crystal structure and phase transitions of guanidinium trichlorostannate, C(NH 2 ) 3 SnCl 3 . At 295 K the crystal structure is orthorhombic, space group Pbca, Z=8, a=7.7506(2) A, b=12.0958(4) A and c=17.8049(6) A, solved from single-crystal data. It is perovskite-like with distorted corner-linked SnCl 6 octahedra and with ordered guanidinium cations in the distorted cuboctahedral voids. At 400 K the structure shows a first-order order-disorder phase transition. The space group is changed to Pnma with Z=4, a=12.1552(2) A, b=8.8590(2) A and c=8.0175(1) A, solved from powder diffraction data and showing disordering of the guanidinium cations. At 419 K, the structure shows yet another first-order order-disorder transformation with disordering of the SnCl 3 - part. The space group symmetry is maintained as Pnma, with a=12.1786(2) A, b=8.8642(2) A and c=8.0821(2) A. The thermodynamic parameters of these transitions and the p-T phase diagram have been determined and described. - Graphical abstract: The perovskite-like crystals of C(NH 2 ) 3 SnCl 3 undergo two successive first-order phase transitions at 400 and 419 K, both accompanied by an essential order-disorder contribution. The p-T phase diagram exhibits a singular point at 219 MPa and 443 K
Moessbauer determination of magnetic structure of Fe3BO6 crystal
International Nuclear Information System (INIS)
Kovalenko, P.P.; Labushkin, V.G.; Ovsepyan, A.K.; Sarkisov, Eh.R.; Smirnov, E.V.; Prokopov, A.R.; Seleznev, V.N.
1984-01-01
The magnetic structure of a Fe 3 BO 6 crystal belonging to space group Dsub(2h)sup(16)(Psub(nma)) is determined by the Moessbauer γ-radiation diffraction. The bragg reflection (700) of Moessbauer 14.4 keV γ-quanta from the Fe 3 BO 6 monocrystal has been studied experimentally. A high sensitivity of the interference of γ-quantum diffraction scattering on Fe nuclei being in crystallographically non-equivalent 8d- and 4s-positions to the type of magnetic ordering in the crystal is used for determination of the magnetic structure. Agreement of the experimental results with the theoretical calculations, conducted for types of magnetic ordering resolved by the symmetry of the crystal, permitted to reliably determine the magnetic structure of this compound. The results obtained confirm the data of neutrondiffraction studies on magnetic ordering in Fe 3 BO 6 . Advantages of the Moessbauer-diffraction study, as compared to the magnetic neutrondiffraction method, in particular, for investigation of crystals, in which the hyperfine magnetic fields on Fe nuclei have different values, are revealed and discussed in detail
The crystal structure and the phase transitions of pyridinium trifluoromethanesulfonate
International Nuclear Information System (INIS)
Jesariew, Dominik; Ilczyszyn, Maria M; Pietraszko, Adam
2014-01-01
The calorimetric and optical studies and the structural properties of pyridinium trifluoromethanesulfonate (abbreviated as PyHOTf) are reported. A sequence of four fully reversible solid–solid phase transitions, at 223.0, 309.0, 359.9 and 394.3 K, has been discovered. The phase transition sequence was confirmed by x-ray diffraction data. The crystal structures of three phases (V, IV and III) have been determined from the single crystal x-ray diffraction data. Structural properties of the high temperature phases are characterized using powder x-ray diffraction data measured in the 290–425 K temperature range. The structural changes triggered by the temperature change are discussed in relation to the phase transitions. Two low temperature phases (V and IV) belong to the P4 3 2 1 2 space group of the tetragonal system. The intermediate phases (III and II) are monoclinic and the prototype high temperature phase (I) is a pseudo-cubic (tetragonal) one. The low temperature phases (V and IV) are well ordered. The crystal structure of intermediate (III and II) and prototype (I) phases are characterized by high disorder of the pyridinium cations and triflate anions. (papers)
International Nuclear Information System (INIS)
Han, Y.; Cang, H.-X.; Zhou, J.-X.; Wang, Y.-P.; Bi, R.-C.; Colelesage, J.; Delbaere, L.T.J.; Nahoum, V.; Shi, R.; Zhou, M.; Zhu, D.-W.; Lin, S.-X.
2004-01-01
The crystallization of 16 proteins was carried out using 60 wells on board Shenzhou 3 in 2002. Although the mission was only 7 days, careful and concerted planning at all stages made it possible to obtain crystals of improved quality compared to their ground controls for some of the proteins. Significantly improved resolutions were obtained from diffracted crystals of 4 proteins. A complete data set from a space crystal of the PEP carboxykinase yielded significantly higher resolution (1.46 A vs. 1.87 A), I/sigma (22.4 vs. 15.5), and a lower average temperature factor (29.2 A 2 vs. 42.9 A 2 ) than the best ground-based control crystal. The 3-D structure of the enzyme is well improved with significant ligand density. It has been postulated that the reduced convection and absence of macromolecule sedimentation under microgravity have advantages/benefits for protein crystal growth. Improvements in experimental design for protein crystal growth in microgravity are ongoing
The crystal structure of tris(thenoyltrifluoroacetonato)bis(triphenylphosphine oxide)neodymium(III)
International Nuclear Information System (INIS)
Leipoldt, J.G.; Bok, L.D.C.; Laubscher, A.E.; Basson, S.S.
1975-01-01
The crystal structure of tris(thenoyltrifluoroacetonato)bis= x (triphenylphosphine oxide)neodymium(III), (Nd(TTa) 3 .2TPPO), has been determined by single crystal X-ray diffraction. A total number of 5505 independent reflections was used for the structure determination. The complex crystallized in the triclinic space group P 1 - with two molecules in the unit cell. The cell dimensions are a = 23.64 A, b Z= 12.15 A, C 11.19 A, α = 109.4 0 , β = 104.2 0 , γ = 90.8 0 . The final calculated R vale is 8.4%. The molecule is monomeric and the neodymium atom is coordinated to eight oxygen atoms (six from the three thenoyltrifluoroacetone groups and two from the two triphenylphosphine groups) which form a dodecahedron. The average neodymium-oxygen bond length is 2.44 A. (author)
Crystallization and preliminary X-ray structural studies of adeno-associated virus serotype 6
International Nuclear Information System (INIS)
Xie, Qing; Ongley, Heather M.; Hare, Joan; Chapman, Michael S.
2008-01-01
Adeno-associated virus type 6, a human DNA virus that is being developed as a vector for gene therapy, has been crystallized in a form suitable for structure determination at about 3.2 Å resolution. Adeno-associated viruses are being developed as vectors for gene therapy and have been used in a number of clinical trials. Vectors to date have been based on the type species AAV-2, the structure of which was published in 2002. There is growing interest in modulating the cellular tropism and immune neutralization of AAV-2 with variants inspired by the properties of other serotypes. Towards the determination of a structure for AAV type 6, this paper reports the high-yield production, purification, crystallization and preliminary diffraction studies of infectious AAV-6 virions. The crystals diffracted to 3.2 Å resolution using synchrotron radiation. The most promising crystal form belonged to space group R3 and appeared to be suitable for initial structure determination
Karthigha, S.; Krishnamoorthi, C.
2018-03-01
An organic quinolinium derivative nonlinear optical (NLO) crystal, 1-ethyl-2-[2-(4-nitro-phenyl)-vinyl]-quinolinium iodide (PNQI) was synthesized and successfully grown by slow evaporation solution growth technique. Formation of a crystalline compound was confirmed by single crystal X-ray diffraction. The quinolinium compound PNQI crystallizes in the triclinic crystal system with a centrosymmetric space group of P-1 symmetry. The molecular structure of PNQI was confirmed by 1H NMR and 13C NMR spectral studies. The thermal properties of the crystal have been investigated by thermogravimetric (TG) and differential scanning calorimetry (DSC) studies. The optical characteristics obtained from UV-Vis-NIR spectral data were described and the cut-off wavelength observed at 506 nm. The etching study was performed to analyse the growth features of PNQI single crystal. The third order NLO properties such as nonlinear refractive index (n2), nonlinear absorption coefficient (β) and nonlinear susceptibility (χ (3)) of the crystal were investigated using Z-scan technique at 632.8 nm of Hesbnd Ne laser.
Crystal structure, conformational analysis, and molecular dynamics of tetra-0-methyl-(+)-catechin
Frank R. Fronczek; Richard W. Hemingway; G. Wayne McGraw; Jan P. Steynberg; Carin A. Helfer; Wayne L. Mattice
1993-01-01
The structure of tetra-O-methyl-(+)-catechin has been determined in the crystalline state. Two independent molecules, denoted structure A and structure B, exist in the unit cell. Crystals are triclinic, space group P1, a=4.8125(2) Ǻ, b=12.9148(8) Ǻ, c=13.8862(11) Ǻ, α=86.962(6)°, β=89.120(5)°, γ=...
The crystal structure of bøgvadite (Na2SrBa2Al4F20)
DEFF Research Database (Denmark)
Balic Zunic, Tonci
2014-01-01
The crystal structure of bøgvadite, Na2SrBa2Al4F20, has been solved and refined to a R1 factor of 4.4% from single-crystal data (MoKα X-ray diffraction, CCD area detector) on a sample from the cryolite deposit at Ivittuut, SW Greenland. Bøgvadite is monoclinic, P21/n space group, with unit cell...... parameters a= 7.134(1), b= 19.996(3) and c= 5.3440(8) Å, β = 90.02(1)o. A close proximity of the crystal structure to an orthorhombic symmetry and the presence of the two twin components in a nearly 1:1 ratio suggest that the investigated bøgvadite crystal has originally formed as a high......-temperature orthorhombic polymorph which on cooling transformed to the stable low temperature monoclinic structure. The bøgvadite crystal structure has groupings of cation-fluoride coordination polyhedra similar to those found in the crystal structures of the genetically closely associated minerals jarlite...
Crystal growth and structure of KLnP/sub 4/O/sub 12/
International Nuclear Information System (INIS)
Guangyan, H.; Shuzhen, L.; Shuying, Y.; Mingyu, C.
1985-01-01
Potassium rare earth tetraphosphates KLnP/sub 4/O/sub 12/ are a kind of polyphosphates of rare earths with unique properties and structures. KNdP/sub 4/O/sub 12/ is a high-Nd-concentration laser material with a non-centrosymmetric space group P2, yielding linear and nonlinear optical properties. α-KErP/sub 4/O/sub 12/ might be used as a material for engineering device purpose. KTbP/sub 4/O/sub 12/ can emit strong green fluorescence, it might be a kind of a new crystal material for laser or luminescence. In order to search for new crystal materials and to study the correlations among the composition, structures and the properties of rare earth compounds, the crystal growth of KLnP/sub 4/O/sub 12/ and their structures are studied in this paper
Weselinski, Lukasz; Luebke, Ryan; Eddaoudi, Mohamed
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Kuhn, Paul-Steffen; Bü chel, Gabriel E.; Jovanović, Katarina K.; Filipović, Lana; Radulović, Siniša; Rapta, Peter; Arion, Vladimir B.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Pump, Eva
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Pump, Eva
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Anneser, Markus R.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Abdul Halim, Racha Ghassan
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Bootharaju, Megalamane Siddaramappa
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wu, Melissa M.; Gill, Arran M.; Yunpeng, Lu; Yongxin, Li; Ganguly, Rakesh; Falivene, Laura; Garcí a, Felipe
2017-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wu, Melissa M.; Gill, Arran M.; Yunpeng, Lu; Yongxin, Li; Ganguly, Rakesh; Falivene, Laura; Garcí a, Felipe
2017-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wu, Melissa M.; Gill, Arran M.; Yunpeng, Lu; Yongxin, Li; Ganguly, Rakesh; Falivene, Laura; Garcí a, Felipe
2017-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wu, Melissa M.; Gill, Arran M.; Yunpeng, Lu; Yongxin, Li; Ganguly, Rakesh; Falivene, Laura; Garcí a, Felipe
2017-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Vummaleti, Sai V. C.; Nelson, David J.; Poater, Albert; Gó mez-Suá rez, Adriá n; Cordes, David B.; Slawin, Alexandra M. Z.; Nolan, Steven P.; Cavallo, Luigi
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Soldan, Giada
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Shekhah, Osama; Belmabkhout, Youssef; Chen, Zhijie; Guillerm, Vincent; Cairns, Amy; Adil, Karim; Eddaoudi, Mohamed
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Vummaleti, Sai V. C.; Nelson, David J.; Poater, Albert; Gó mez-Suá rez, Adriá n; Cordes, David B.; Slawin, Alexandra M. Z.; Nolan, Steven P.; Cavallo, Luigi
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Vummaleti, Sai V. C.; Nelson, David J.; Poater, Albert; Gó mez-Suá rez, Adriá n; Cordes, David B.; Slawin, Alexandra M. Z.; Nolan, Steven P.; Cavallo, Luigi
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
El-Assaad, Tarek H.; Auer, Manuel; Castañ eda, Raul; Hallal, Kassem M.; Jradi, Fadi M.; Mosca, Lorenzo; Khnayzer, Rony S.; Patra, Digambara; Timofeeva, Tatiana V.; Bredas, Jean-Luc; List-Kratochvil, Emil J. W.; Wex, Brigitte; Kaafarani, Bilal R.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Zhijie
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Zhijie
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Zhijie
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Tong, Guanghu
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Li, Shenyu
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Yang, Wenguo
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Yang, Xuejin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Yao, Liang-Feng
2012-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Li, Shenyu
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Li, Shenyu
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Liu, Yanpin
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Lu, Hai-Sheng
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Eubank, Jarrod F.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jian, Zhongbao
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Crystal structure and magnetic properties of Tb6FeSb2
International Nuclear Information System (INIS)
Cai Gemei; Zhang Jiliang; He Wei; Qin Pingli; Zeng Lingmin
2006-01-01
The crystal structure and magnetic properties of Tb 6 FeSb 2 has been investigated for the first time. The compound crystallizes in the hexagonal, space group P6-bar 2m (No. 189) with the Ho 6 FeSb 2 structure type and lattice parameters a=8.1942(5)A, c=4.1758(3)A, z=1 and D calc =8.564g/cm 3 . Its magnetic properties were measured between 85 and 420K. The Curie temperature T c =256K was obtained using the method of intersecting tangents, and the effective paramagnetic moment was μ eff =9.32μ B per Tb atom
Vijayalakshmi, A.; Vidyavathy, B.; Vinitha, G.
2016-08-01
Isonicotinamide p-nitrophenol (ICPNP), a new organic material, was synthesized using methanol solvent. Single crystals of ICPNP were grown using a slow evaporation solution growth technique. Crystal structure of ICPNP is elucidated by single crystal X-ray diffraction analysis. It belongs to monoclinic crystal system with space group of P21/c. It forms two dimensional networks by O-H…O, N-H…O and C-H…O hydrogen bonds. The molecular structure of ICPNP was further confirmed by Fourier transform infrared (FTIR) spectral analysis. The optical transmittance range and the lower cut-off wavelength (421 nm) with the optical band gap (2.90 eV) of the ICPNP crystal were determined by UV-vis-NIR spectral study. Thermal behavior of ICPNP was studied by thermo gravimetric and differential thermal analyses (TG/DTA). The relative dielectric permittivity was calculated for various temperature ranges. Laser damage threshold of ICPNP crystal was found to be 1.9 GW/cm2 using an Nd:YAG laser. A Z-scan technique was employed to measure the nonlinear absorption coefficient, nonlinear refractive index and nonlinear optical susceptibility. Optical limiting behavior of ICPNP was observed at 35 mW input power.
Space growth studies of Ce-doped Bi12SiO20 single crystal
International Nuclear Information System (INIS)
Zhou, Y.F.; Wang, J.C.; Tang, L.A.; Pan, Z.L.; Chen, N.F.; Chen, W.C.; Huang, Y.Y.; He, W.
2004-01-01
Ce-doped Bi 12 SiO 20 (BSO) single crystal was grown on board of the Chinese Spacecraft-Shenzhou No. 3. A cylindrical crystal, 10 mm in diameter and 40 mm in length, was obtained. The morphology of crystals is significantly different for ground- and space-grown portions. The space- and ground-grown crystals have been characterized by Ce concentration distribution, X-ray rocking curve absorption spectrum and micro-Raman spectrum. The results show that the quality of Ce-doped BSO crystal grown in space is more homogeneous and more perfect than that of ground grown one
Icosahedral symmetry described by an incommensurately modulated crystal structure model
DEFF Research Database (Denmark)
Wolny, Janusz; Lebech, Bente
1986-01-01
A crystal structure model of an incommensurately modulated structure is presented. Although six different reciprocal vectors are used to describe the model, all calculations are done in three dimensions making calculation of the real-space structure trivial. Using this model, it is shown that both...... the positions of the bragg reflections and information about the relative intensities of these reflections are in full accordance with the diffraction patterns reported for microcrystals of the rapidly quenched Al86Mn14 alloy. It is also shown that at least the local structure possesses full icosahedral...
International Nuclear Information System (INIS)
Eerde, André van; Wolterink-van Loo, Suzanne; Oost, John van der; Dijkstra, Bauke W.
2006-01-01
E. coli bacterioferritin was crystallized in a novel crystal form from different conditions and the structure was solved. The crystals belonged to space group P2 1 3 and diffracted to a resolution of 2.5 Å. Escherichia coli bacterioferritin was serendipitously crystallized in a novel cubic crystal form and its structure could be determined to 2.5 Å resolution despite a high degree of merohedral twinning. This is the first report of crystallographic data on ‘as-isolated’ E. coli bacterioferritin. The ferroxidase active site contains positive difference density consistent with two metal ions that had co-purified with the protein. X-ray fluorescence studies suggest that the metal composition is different from that of previous structures and is a mix of zinc and native iron ions. The ferroxidase-centre configuration displays a similar flexibility as previously noted for other bacterioferritins
Growth and structure of a new photonic crystal: Chlorine substituted chalcone
Energy Technology Data Exchange (ETDEWEB)
Sarveshwara, H. P., E-mail: sarvesh.heggadde@gmail.com; Menezes, Anthoni Praveen [Department of Physics, Mangalore Institute Of Technology And Engineering (MITE), Moodabidri-574225 (India); Raghavendra, S.; Dharmaprakash, S. M. [Department of Studies in Physics, Mangalore University, Mangalore -575199 (India); A, Jayarama [Department of Physics, Sadguru Swami Nithyananda Institute of Technology (SSNIT), Kanhangad 671315 (India)
2015-06-24
A new organic photonic material 3-(2, 4-dichlorophenyl)-1-(2,5-dimethylthiophen-3-yl)propan-1-one(DMTP) has been synthesized and crystallised in acetone solution. The functional groups present in the new material were identified by FTIR spectroscopy. The material is optically transparent in the wavelength range of 400–1100 nm. The crystal structure of DMTP was determined by single crystal X-ray diffraction. The title compound crystallizes in monoclinic system with a centrosymmetric space group P2{sub 1}/c. The Z-scan study revealed that the optical limiting property exhibited by the DMTP molecule is based on the reverse saturable absorption phenomena.
Crystal structure and thermal behavior of KB3O6
International Nuclear Information System (INIS)
Bubnova, R.S.; Fundamenskij, V.S.; Filatov, S.K.; Polyakova, I.G.
2004-01-01
The structure of potassium triborate prepared in metastable state by crystallization from melt at ∼ 800 deg C was studied by the method of X-ray diffraction analysis. It was ascertained that KB 3 O 6 belongs to monoclinic crystal system, space group P2 1 /c, a = 9.319(1), b = 6.648(1), c = 21.094(2) A, β = 94.38(1) deg, Z = 12. The compound is referred to a new structural type. Anion of the structure is a single boron-oxygen frame formed by three independent rigid triborate rings of [B 3 O 5 ] - , each of them consisting of two BO 3 triangles and BO 4 tetrahedron. Phase transformations during KB 3 O 6 heating up to 800 deg C, as well as thermal expansion in the range of 20-650 deg C, were studied [ru
Amine free crystal structure: The crystal structure of d(CGCGCG)2 and methylamine complex crystal
International Nuclear Information System (INIS)
Ohishi, Hirofumi; Tsukamoto, Koji; Hiyama, Yoichi; Maezaki, Naoyoshi; Tanaka, Tetsuaki; Ishida, Toshimasa
2006-01-01
We succeeded in the crystallization of d(CGCGCG) 2 and methylamine Complex. The crystal was clear and of sufficient size to collect the X-ray crystallographic data up to 1.0 A resolution using synchrotron radiation. As a result of X-ray crystallographic analysis of 2F o - F c map was much clear and easily traced. It is First time monoamine co-crystallizes with d(CGCGCG) 2 . However, methylamine was not found from the complex crystal of d(CGCGCG) 2 and methylamine. Five Mg ions were found around d(CGCGCG) 2 molecules. These Mg ions neutralized the anion of 10 values of the phosphate group of DNA with five Mg 2+ . DNA stabilized only by a metallic ion and there is no example of analyzing the X-ray crystal structure like this. Mg ion stabilizes the conformation of Z-DNA. To use monoamine for crystallization of DNA, we found that we can get only d(CGCGCG) 2 and Mg cation crystal. Only Mg cation can stabilize the conformation of Z-DNA. The method of using the monoamine for the crystallization of DNA can be applied to the crystallization of DNA of long chain of length in the future like this
Crystal structure of the Al2CuIr phase
International Nuclear Information System (INIS)
Meshi, L.; Ezersky, V.; Kapush, D.; Grushko, B.
2010-01-01
A new ternary Al 2 CuIr phase was revealed in the Al-Cu-Ir system. It is formed below 1063 o C from the β-phase (CsCl-type structure) extending at elevated temperatures from AlIr. The crystal structure of the Al 2 CuIr phase was determined using a combination of precession electron diffraction and X-ray powder diffraction techniques. The phase has an orthorhombic C-centered unit cell with lattice parameters a = 8.1196(7) A, b = 5.0646(2) A and c = 5.18513(3) A; its crystal symmetry can be described by the Cmme (no. 67) space group (Pearson symbol oC16). The unit cell of the new phase contains 8 Al, 4 Cu and 4 Ir atoms and exhibits a new structure type. The reliability factors characterizing the Rietveld refinement procedure are: R p = 4.45%, R wp = 6.45%, R B = 3.69% and R f = 2.41%.
Crystal structure of ferroelectric Bi{sub 2}VO{sub 5.5}
Energy Technology Data Exchange (ETDEWEB)
Sooryanarayana, K.; Guru Row, T.N.; Varma, K.B.R. [Indian Inst. of Science, Bangalore (India)
1997-12-01
The structure of the {alpha}-phase of bismuth vanadate Bi{sub 2}VO{sub 5.5} has been determined using single crystal X-ray diffraction data in the space group Aba2. The refinement involves a well defined disorder at the vanadium site, which incorporates the features of the superlattice structure with vanadium tetrahedra and oxygen-deficient octahedra that is displaced about the twofold axis.
Crystal structure of bassetite and saleeite. New insight into autunite-group minerals
Energy Technology Data Exchange (ETDEWEB)
Dal Bo, Fabrice; Hatert, Frederic [Liege Univ. (Belgium). Lab. de Mineralogie; Mees, Florias [Royal Museum for Central Africa, Tervuren (Belgium); Philippo, Simon [Musee National d' Histoire Naturelle, Luxembourg (Luxembourg). Section Mineralogie; Baijot, Maxime; Fontaine, Francois [Liege Univ. (Belgium). Dept. de Geologie
2016-06-15
The crystal structures of two autunite-group minerals have been solved recently. The crystal structure of bassetite, Fe{sup 2+}[(UO{sub 2})(PO{sub 4})]{sub 2}(H{sub 2}O){sub 10}, from the type locality in Cornwall, United Kingdom (Basset Mines) was solved for the first time. Bassetite is monoclinic, space group P2{sub 1}/n, a = 6.961(1), b = 20.039(2), c = 6.974(1) Aa and β = 90.46(1) . The crystal structure of saleeite, Mg[(UO{sub 2})(PO{sub 4})]{sub 2}(H{sub 2}O){sub 10}, from Shinkolobwe, Democratic Republic of Congo, was also solved. Saleeite is monoclinic, space group P2{sub 1}/n, a = 6.951(1), b = 19.942(1), c = 6.967(1) Aa and β = 90.58(1) . The crystal structure investigation of bassetite (R{sub 1} = 0.0658 for 1879 observed reflections with vertical stroke F{sub o} vertical stroke ≥ 4σ{sub F}) and saleeite (R{sub 1} = 0.0307 for 1990 observed reflections with vertical stroke F{sub o} vertical stroke ≥ 4σ{sub F}) confirms that both minerals are topologically identical and that bassetite contains ten water molecules per formula unit. Their structure contains autunite-type sheets, [(UO{sub 2})(PO{sub 4})]{sup -}, consisting of corner-sharing UO{sub 6} square bipyramids and PO{sub 4} tetrahedra. Iron and magnesium are surrounded by water molecules to form Fe(H{sub 2}O){sub 6} or Mg(H{sub 2}O){sub 6} octahedra located in interlayer, between the autunite-type sheets. Two isolated independent water molecules are also located in interlayer. Energy-dispersive X-ray spectroscopy analysis confirmed the chemical composition obtained from structure refinement. These new data prompt a re-assessment of minerals of the autunite and meta-autunite groups.
Synthesis and crystal structure of two lead (II) complexes with 1,10-phenanthroline ligand
International Nuclear Information System (INIS)
Olivera, Fiorella L.; Santillan, Guillermo A.
2012-01-01
Two coordination complexes have been synthesized by the reaction of lead nitrate (II) with 1,10-phenanthroline in methanol/water. The crystals of these complexes were obtained by using the diffusion method and structurally characterized by X-ray single crystal diffraction. Both complexes crystallized in the monoclinic space group P2 1 /c. The analysis by crystal X-ray diffraction reveals that in both complexes the coordination around the lead (II) ion is a distorted octahedral structure where the ion is bonded to the heterocyclic nitrogen atoms of chelating ligand 1,10-phenanthroline, three oxygen atoms of three nitrate groups and one oxygen from the water molecule. The difference between the complexes lies in the way of nitrate ion in presence of carboxylic acid aromatics. In addition, the crystal structure of complexes can be regarded as a 3D coordination polymer through Pb-O weak interactions, hydrogen bonds and π-π stacking interactions. (author).
Energy Technology Data Exchange (ETDEWEB)
Sikora, W
1974-10-15
A description of magnetic structures based on the use of representations of space groups is given. Representations of the space groups were established for each compound on the basis of experimental data by the method of projection operators. The compounds contained in the list are collected according to crystal systems, alphabetically within each system. The description of each compound consists of the four parts. The first part contain the chemical symbol of the compound, the second its space group. The next part contains the chemical symbol of the magnetic atom and its positions in Wychoff notation with the number of equivalent positions in the crystal unit cell. The main description of a compound magnetic structure is given in the fourth part. It contains: K vector defined in the reciprocal space, the representation according to which a magnetic structure is transformed and the axial vector function S which describes the magnetic structure.
Crystal structure of a novel cerium indide Ce{sub 6}Pt{sub 11}In{sub 14}
Energy Technology Data Exchange (ETDEWEB)
Stepien-Damm, J.; Bukowski, Z.; Zaremba, V.I.; Pikul, A.P.; Kaczorowski, D
2004-10-06
The crystal structure of a new intermetallic compound Ce{sub 6}Pt{sub 11}In{sub 14} has been determined from single crystal X-ray data and was refined by a full-matrix least-squares method down to R{sub 1}=0.0497 for 1215 structure factors and 96 parameters. The unit cell is monoclinic, space group C2/m, Z=2 with the lattice parameters: a=22.729(5) A, b=4.3960(10) A, c=14.780(3) A and {beta}=118.35(3) deg. . It represents a new type of crystal structure of intermetallic compounds.
Crystal structure of the new ternary thorium indide Th{sub 4}Pd{sub 10}In{sub 21}
Energy Technology Data Exchange (ETDEWEB)
Hlukhyy, V.; Zaremba, V.; Stepien-Damm, J.; Troc, R
2003-03-24
The structure of Th{sub 4}Pd{sub 10}In{sub 21} was refined from single crystal X-ray diffraction data. The compound crystallizes in the monoclinic system, space group C2/m, mC70; with lattice parameters a=23.024(5) A, b=4.512(1) A, c=17.224(3) A, {beta}=124.57(3) deg. The crystal structure was refined using the SHELXL-97 program (R{sub 1}=0.0477, 2561 F{sup 2} values for 108 variables). This compound adopts the Ho{sub 4}Ni{sub 10}Ga{sub 21}-type structure. The crystal chemistry and relationships of this phase to other ones are briefly discussed.
Arjunan, V.; Kalaivani, M.; Marchewka, M. K.; Mohan, S.
2013-08-01
The crystal structure investigations of melamine with phosphorous acid, namely melaminium dihydrogenphosphite monohydrate (C3N6H7·H2PO3·H2O) have been investigated by means of single crystal X-ray diffraction method. The title compound crystallizes in monoclinic crystal system, and the space group is P21/c with a = 10.069 Å, b = 21.592 Å, c = 12.409 Å and Z = 12. The vibrational assignments and analysis of melaminium dihydrogen phosphite monohydrate have also been performed by FTIR, FT-Raman and far-infrared spectral studies. The quantum chemical simulations were performed with DFT (B3LYP) method using 6-31G**, cc-pVTZ, and 6-311++G** basis sets to determine the energy, structural, thermodynamic parameters and vibrational frequencies of melaminium dihydrogen phosphite monohydrate. The hydrogen atom from phosphorous acid was transferred to the melamine molecule giving the singly protonated melaminium cation. The ability of ions to form spontaneous three-dimensional structure through weak Osbnd H···O and Nsbnd H···O hydrogen bonds shows notable vibrational effects.
Structural and electrical properties of organic stilbazolium single crystal of DSCHS
Sundaram, S. John; Raj, A. Antony; Ramaclus, Jerald V.; Sagayaraj, P.
2016-05-01
Organic nonlinear optical crystal 4-N, N-Dimethyl Amino-4'N'-Methyl-Stilbazolium 3-Carboxy-4-Hydroxy benzenesulfonate (DSCHS) has been successfully grown from aqueous methanol solution by adopting slow solvent evaporation technique. Chemical composition of the sample was confirmed by CHN analysis. Powder X-ray diffraction analysis was carried out and it shows that DSCHS crystal belongs to triclinic structure with Pl space group. It is found that this material exhibits positive photoconductivity. Dielectric studies were also carried out for different temperature by varying the frequency.
Photonic Crystal Laser-Driven Accelerator Structures
International Nuclear Information System (INIS)
Cowan, B
2004-01-01
The authors discuss simulated photonic crystal structure designs for laser-driven particle acceleration. They focus on three-dimensional planar structures based on the so-called ''woodpile'' lattice, demonstrating guiding of a speed-of-light accelerating mode by a defect in the photonic crystal lattice. They introduce a candidate geometry and discuss the properties of the accelerating mode. They also discuss the linear beam dynamics in the structure present a novelmethod for focusing the beam. In addition they describe ongoing investigations of photonic crystal fiber-based structures
Synthesis and crystal structure of MgB12
International Nuclear Information System (INIS)
Adasch, Volker; Hess, Kai-Uwe; Ludwig, Thilo; Vojteer, Natascha; Hillebrecht, Harald
2006-01-01
Single crystals of MgB 12 were synthesized from the elements in a Mg/Cu melt at 1600deg. C. MgB 12 crystallizes orthorhombic in space group Pnma with a=16.632(3)A, b=17.803(4)A and c=10.396(2)A. The crystal structure (Z=30, 5796 reflections, 510 variables, R 1 (F)=0.049, wR 2 (I)=0.134) consists of a three dimensional net of B 12 icosahedra and B 21 units in a ratio 2:1. The B 21 units are observed for the first time in a solid compound. Mg is on positions with partial occupation. The summation reveals the composition MgB 12.35 or Mg 0.97 B 12 , respectively. This is in good agreement with the value of MgB 11.25 as expected by electronic reasons to stabilize the boron polyhedra B 12 2- and B 21 4-
Directory of Open Access Journals (Sweden)
J. Piątkowski
2009-07-01
Full Text Available Adding high-melting point elements (Mo, Nb, Ni, Ti, W to complex silumins results in hardening of the latter ones, owing to the formation of new intermetallic phases of the AlxMey type, with refinement of dendrites in α solution and crystals in β phase. The hardening is also due to the effect of various inoculants. An addition of the inoculant is expected to form substrates, the crystal lattice of which, or some (privileged lattice planes and interatomic spaces should bear a strong resemblance to the crystal nucleus. To verify this statement, using binary phase equilibria systems, the coefficient of crystal lattice matching, being one of the measures of the crystallographic similarity, was calculated. A compatibility of this parameter (up to 20% may decide about the structure compatibility between the substrate and crystal which, in turn, is responsible for the effectiveness of alloy modification. Investigations have proved that, given the temperature range of their formation, the density, the lattice type, and the lattice parameter, some intermetallic phases of the AlxMey type can act as substrates for the crystallisation of aluminium and silicon, and some of the silumin hardening phases.
Ba3NbAs3O: synthesis, crystal structure, Raman spectroscopy and bonding analysis
International Nuclear Information System (INIS)
Monconduit, L.; Tillard, M.; Favier, F.; Belin, C.
1999-01-01
The crystal structure of Ba 3 NbAs 3 O has been solved by crystal X-ray analysis (CAD-4 automatic diffractometer, Mo Kα radiation). The compound crystallizes in space group Pnma, a=6.724(2), b=11.100(2), c=13.462(3) A, V=1004.7(4) A 3 , Z=4. The structure has been refined to R1=0.0343 for 964 independent reflections, it can be described as packing of nearly tetrahedral NbAs 3 O 6- anions, their coordination by Ba 2+ cations forming interconnected trigonal prisms. The chemical bonding has been analyzed by MO calculations and Raman spectroscopy. (orig.)
Crystal structure determination of Efavirenz
International Nuclear Information System (INIS)
Popeneciu, Horea; Dumitru, Ristoiu; Tripon, Carmen; Borodi, Gheorghe; Pop, Mihaela Maria
2015-01-01
Needle-shaped single crystals of the title compound, C 14 H 9 ClF 3 NO 2 , were obtained from a co-crystallization experiment of Efavirenz with maleic acid in a (1:1) ratio, using methanol as solvent. Crystal structure determination at room temperature revealed a significant anisotropy of the lattice expansion compared to the previously reported low-temperature structure. In both low- and room temperature structures the cyclopropylethynyl fragment in one of the asymmetric unit molecules is disordered. While at low-temperature only one C atom exhibits positional disorder, at room temperature the disorder is present for two C atoms of the cyclopropane ring
Stevens, Loah A.; Goertz, Katelyn P.; Fonari, Alexandr; Shu, Ying; Williamson, Rachel M.; Bredas, Jean-Luc; Coropceanu, Veaceslav; Jurchescu, Oana D.; Collis, Gavin E.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Cadiau, Amandine
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wu, Melissa M.; Gill, Arran M.; Yunpeng, Lu; Yongxin, Li; Ganguly, Rakesh; Falivene, Laura; Garcí a, Felipe
2017-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Joshi, Chakra Prasad
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Kole, G.K.; Cairns, A.J.; Eddaoudi, Mohamed; Vittal, J.J.
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Hu, Pan; Lee, Sangsu; Seng, Herng Tun; Aratani, Naoki; Zheng, Bin; Yamada, Hiroko; Huang, Kuo-Wei; Ding, Jun; Kim, Dongho; Wu, Jishan
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Kuhn, Paul-Steffen; Cremer, Laura; Gavriluta, Anatolie; Jovanović, Katarina K.; Filipović, Lana; Hummer, Alfred A.; Bü chel, Gabriel E.; Dojčinović, Biljana P.; Meier, Samuel M.; Rompel, Annette; Radulović, Siniša; Tommasino, Jean Bernard; Luneau, Dominique; Arion, Vladimir B.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Lou, Xin-Hua; Xu, Chen; Li, Hong-Mei; Wang, Zhi-Qiang; Guo, Hui; Xue, Dongxu
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Davaasuren, Bambar; Padhy, Harihara; Rothenberger, Alexander
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Roesle, Philipp; Caporaso, Lucia; Schnitte, Manuel; Goldbach, Verena; Cavallo, Luigi; Mecking, Stefan
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Neuwald, B.; Falivene, L.; Caporaso, L.; Cavallo, Luigi; Mecking, S.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Neuwald, B.; Falivene, L.; Caporaso, L.; Cavallo, Luigi; Mecking, S.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wu, Melissa M.
2017-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Li, Shenyu
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Dentel, H.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Cadiau, Amandine
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Yang, Wenguo
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Urbina-Blanco, C.A.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Liu, Yanpin; Chen, Chaohuang; Li, Huaifeng; Huang, Kuo-Wei; Tan, Jianwei; Weng, Zhiqiang
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Savage, Mathew; da Silva, Ivan; Johnson, Mark; Carter, Joseph H.; Newby, Ruth; Suetin, Mikhail; Besley, Elena; Manuel, Pascal; Rudić, Svemir; Fitch, Andrew N.; Murray, Claire; David, William I. F.; Yang, Sihai; Schrö der, Martin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Nielsen, Christian B.; White, Andrew J. P.; McCulloch, Iain
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zhang, Jing; Ajitha, Manjaly John; He, Lin; Liu, Kai; Dai, Bin; Huang, Kuo-Wei
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Yang, Xuejin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Lakshminarayana, Arun Naibi; Chang, Jingjing; Luo, Jie; Zheng, Bin; Huang, Kuo-Wei; Chi, Chunyan
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Luo, Feng
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Synthesis and crystal structure of lithium beryllium deuteride Li2BeD4.
Bulychev, Boris M; Shpanchenko, Roman V; Antipov, Evgeny V; Sheptyakov, Denis V; Bushmeleva, Svetlana N; Balagurov, Anatoly M
2004-10-04
Single-phase ternary deuteride Li(2)BeD(4) was synthesized by a high-pressure high-temperature technique from LiD and BeD(2). The crystal structure of Li(2)BeD(4) was solved from X-ray and neutron powder diffraction data. The compound crystallizes in the monoclinic space group P2(1)/c with lattice parameters a = 7.06228(9) A, b = 8.3378(1) A, c = 8.3465(1) A, beta =93.577(1) degrees, and Z = 8. Its structure contains isolated BeD(4) tetrahedra and Li atoms that are located in the structure interstices. Li(2)BeD(4) does not undergo any structural phase transitions at temperatures down to 8 K.
Broken symmetry within crystallographic super-spaces: structural and dynamical aspects
International Nuclear Information System (INIS)
Mariette, Celine
2013-01-01
Aperiodic crystals have the property to possess long range order without translational symmetry. These crystals are described within the formalism of super-space crystallography. In this manuscript, we will focus on symmetry breaking which take place in such crystallographic super-space groups, considering the prototype family of n-alkane/urea. Studies performed by X-ray diffraction using synchrotron sources reveal multiple structural solutions implying or not changes of the dimension of the super-space. Once the characterization of the order parameter and of the symmetry breaking is done, we present the critical pre-transitional phenomena associated to phase transitions of group/subgroup types. Coherent neutron scattering and inelastic X-ray scattering allow a dynamical analysis of different kind of excitations in these materials (phonons, phasons). The inclusion compounds with short guest molecules (alkane C n H 2n+2 , n varying from 7 to 13) show at room temperature unidimensional 'liquid-like' phases. The dynamical disorder along the incommensurate direction of these materials generates new structural solutions at low temperature (inter-modulated monoclinic composite, commensurate lock-in). (author) [fr
One dimensional coordination polymers: Synthesis, crystal structures and spectroscopic properties
Karaağaç, Dursun; Kürkçüoğlu, Güneş Süheyla; Şenyel, Mustafa; Şahin, Onur
2016-11-01
Two new one dimensional (1D) cyanide complexes, namely [M(4-aepy)2(H2O)2][Pt(CN)4], (4-aepy = 4-(2-aminoethyl)pyridine M = Cu(II) (1) or Zn(II) (2)), have been synthesized and characterized by vibrational (FT-IR and Raman) spectroscopy, single crystal X-ray diffraction, thermal and elemental analyses techniques. The crystallographic analyses reveal that 1 and 2 are isomorphous and isostructural, and crystallize in the monoclinic system and C2 space group. The Pt(II) ions are coordinated by four cyanide-carbon atoms in the square-planar geometry and the [Pt(CN)4]2- ions act as a counter ion. The M(II) ions display an N4O2 coordination sphere with a distorted octahedral geometry, the nitrogen donors belonging to four molecules of the organic 4-aepy that act as unidentate ligands and two oxygen atoms from aqua ligands. The crystal structures of 1 and 2 are similar each other and linked via intermolecular hydrogen bonding, Pt⋯π interactions to form 3D supramolecular network. Vibration assignments of all the observed bands are given and the spectral features also supported to the crystal structures of the complexes.
Monte Carlo simulation of continuous-space crystal growth
International Nuclear Information System (INIS)
Dodson, B.W.; Taylor, P.A.
1986-01-01
We describe a method, based on Monte Carlo techniques, of simulating the atomic growth of crystals without the discrete lattice space assumed by conventional Monte Carlo growth simulations. Since no lattice space is assumed, problems involving epitaxial growth, heteroepitaxy, phonon-driven mechanisms, surface reconstruction, and many other phenomena incompatible with the lattice-space approximation can be studied. Also, use of the Monte Carlo method circumvents to some extent the extreme limitations on simulated timescale inherent in crystal-growth techniques which might be proposed using molecular dynamics. The implementation of the new method is illustrated by studying the growth of strained-layer superlattice (SLS) interfaces in two-dimensional Lennard-Jones atomic systems. Despite the extreme simplicity of such systems, the qualitative features of SLS growth seen here are similar to those observed experimentally in real semiconductor systems
Structural transitions in crystals of native aspartate carbamoyltransferase
International Nuclear Information System (INIS)
Gouaux, J.E.; Lipscomb, W.N.
1989-01-01
Screened precession x-ray photographs of crystals of native aspartate carbamoyltransferase ligated with L-aspartate and phosphate reveal the presence of a crystal unit-cell dimension that is intermediate between the T (tense) and R (relaxed) states. Characterizing the intermediate (I) crystal is a c-axis unit-cell dimension of 149 angstrom, halfway between the c-axis length of the T (c = 142 angstrom) and R (c = 156 angstrom) states, in the space group P321. Preservation of the P321 space group indicates that the intermediate crystal form retains a threefold axis of symmetry, and therefore the enzyme has at minimum a threefold axis; however, it is not known whether the molecular twofold axis is conserved. The I crystals are formed by soaking T-state crystals with L-aspartate and phosphate. By raising the concentration of L-aspartate the authors can further transform the I crystals, without fragmentation, to a form that has the same unit-cell dimensions as R-state crystals grown in the presence of N-(phosphonoacetyl)-L-aspartate
Crystal structure of bile salt hydrolase from Lactobacillus salivarius.
Xu, Fuzhou; Guo, Fangfang; Hu, Xiao Jian; Lin, Jun
2016-05-01
Bile salt hydrolase (BSH) is a gut-bacterial enzyme that negatively influences host fat digestion and energy harvesting. The BSH enzyme activity functions as a gateway reaction in the small intestine by the deconjugation of glycine-conjugated or taurine-conjugated bile acids. Extensive gut-microbiota studies have suggested that BSH is a key mechanistic microbiome target for the development of novel non-antibiotic food additives to improve animal feed production and for the design of new measures to control obesity in humans. However, research on BSH is still in its infancy, particularly in terms of the structural basis of BSH function, which has hampered the development of BSH-based strategies for improving human and animal health. As an initial step towards the structure-function analysis of BSH, C-terminally His-tagged BSH from Lactobacillus salivarius NRRL B-30514 was crystallized in this study. The 1.90 Å resolution crystal structure of L. salivarius BSH was determined by molecular replacement using the structure of Clostridium perfringens BSH as a starting model. It revealed this BSH to be a member of the N-terminal nucleophile hydrolase superfamily. Crystals of apo BSH belonged to space group P21212, with unit-cell parameters a = 90.79, b = 87.35, c = 86.76 Å (PDB entry 5hke). Two BSH molecules packed perfectly as a dimer in one asymmetric unit. Comparative structural analysis of L. salivarius BSH also identified potential residues that contribute to catalysis and substrate specificity.
Cati, Dilovan S; Stoeckli-Evans, Helen
2017-05-01
The complete mol-ecules of the title compounds, N 2 , N 5 -bis-(pyridin-2-ylmeth-yl)pyrazine-2,5-dicarboxamide, C 18 H 16 N 6 O 2 (I), 3,6-dimethyl- N 2 , N 5 -bis-(pyridin-2-yl-meth-yl)pyrazine-2,5-dicarboxamide, C 20 H 20 N 6 O 2 (II), and N 2 , N 5 -bis-(pyridin-4-ylmeth-yl)pyrazine-2,5-dicarboxamide, C 18 H 16 N 6 O 2 (III), are generated by inversion symmetry, with the pyrazine rings being located about centres of inversion. Each mol-ecule has an extended conformation with the pyridine rings inclined to the pyrazine ring by 89.17 (7)° in (I), 75.83 (8)° in (II) and by 82.71 (6)° in (III). In the crystal of (I), mol-ecules are linked by N-H⋯N hydrogen bonds, forming layers lying parallel to the bc plane. The layers are linked by C-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular structure. In the crystal of (II), mol-ecules are also linked by N-H⋯N hydrogen bonds, forming layers lying parallel to the (10-1) plane. As in (I), the layers are linked by C-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular structure. In the crystal of (III), mol-ecules are again linked by N-H⋯N hydrogen bonds, but here form corrugated sheets lying parallel to the bc plane. Within the sheets, neighbouring pyridine rings are linked by offset π-π inter-actions [inter-centroid distance = 3.739 (1) Å]. The sheets are linked by C-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular structure. Compound (I) crystallizes in the monoclinic space group P 2 1 / c . Another monoclinic polymorph, space group C 2/ c , has been reported on by Cockriel et al. [ Inorg. Chem. Commun. (2008), 11 , 1-4]. The mol-ecular structures of the two polymorphs are compared.
Partial rotational lattice order–disorder in stefin B crystals
International Nuclear Information System (INIS)
Renko, Miha; Taler-Verčič, Ajda; Mihelič, Marko; Žerovnik, Eva; Turk, Dušan
2014-01-01
Crystal lattice disorders are a phenomenon which may hamper the determination of macromolecular crystal structures. Using the case of the crystal structure of stefin B, identification of rotational order–disorder and structure determination are described. At present, the determination of crystal structures from data that have been acquired from twinned crystals is routine; however, with the increasing number of crystal structures additional crystal lattice disorders are being discovered. Here, a previously undescribed partial rotational order–disorder that has been observed in crystals of stefin B is described. The diffraction images revealed normal diffraction patterns that result from a regular crystal lattice. The data could be processed in space groups I4 and I422, yet one crystal exhibited a notable rejection rate in the higher symmetry space group. An explanation for this behaviour was found once the crystal structures had been solved and refined and the electron-density maps had been inspected. The lattice of stefin B crystals is composed of five tetramer layers: four well ordered layers which are followed by an additional layer of alternatively placed tetramers. The presence of alternative positions was revealed by the inspection of electron-density score maps. The well ordered layers correspond to the crystal symmetry of space group I422. In addition, the positions of the molecules in the additional layer are related by twofold rotational axes which correspond to space group I422; however, these molecules lie on the twofold axis and can only be related in a statistical manner. When the occupancies of alternate positions and overlapping are equal, the crystal lattice indeed fulfills the criteria of space group I422; when these occupancies are not equal, the lattice only fulfills the criteria of space group I4
Structural and electrical properties of organic stilbazolium single crystal of DSCHS
International Nuclear Information System (INIS)
Sundaram, S. John; Ramaclus, Jerald V.; Sagayaraj, P.; Raj, A. Antony
2016-01-01
Organic nonlinear optical crystal 4-N, N-Dimethyl Amino-4’N’-Methyl-Stilbazolium 3-Carboxy-4-Hydroxy benzenesulfonate (DSCHS) has been successfully grown from aqueous methanol solution by adopting slow solvent evaporation technique. Chemical composition of the sample was confirmed by CHN analysis. Powder X-ray diffraction analysis was carried out and it shows that DSCHS crystal belongs to triclinic structure with Pl space group. It is found that this material exhibits positive photoconductivity. Dielectric studies were also carried out for different temperature by varying the frequency.
Crystal structure and energy band and optical properties of phosphate Sr3P4O13
International Nuclear Information System (INIS)
Zhang, Y.-C.; Cheng, W.-D.; Wu, D.-S.; Zhang, H.; Chen, D.-G.; Gong, Y.-J.; Kan, Z.-G.
2004-01-01
A single crystal of the compound Sr 3 P 4 O 13 has been found and the crystal structure has been characterized by means of single crystal X-ray diffraction analysis. The compound crystallizes in triclinic system and belongs to space group P1-bar. It builds up from SrO 7 polyhedra and P 4 O 13 -6 anions and has a layered structure, and the Sr atoms are located in the interlayer space. The absorption and luminescence spectrum of Sr 3 P 4 O 13 microcrystals have been measured. The calculated results of crystal energy band structure by the DFT show that the solid state of Sr 3 P 4 O 13 is an isolator with direct band gap. The calculated total and partial density of states indicate that the top valence bands are contributions from P 3p and O 2p states and low conduction bands mostly originate from Sr atomic states. The calculated optical response functions expect that the Sr 3 P 4 O 13 is a low refractive index, and it is possible that the Sr 3 P 4 O 13 is used to make transparent material between the UV and FR light zone
Synthesis, crystal structure and electronic structure of the binary phase Rh{sub 2}Cd{sub 5}
Energy Technology Data Exchange (ETDEWEB)
Koley, Biplab [Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India); Chatterjee, S. [Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India); Jana, Partha P., E-mail: ppj@chem.iitkgp.ernet.in [Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)
2017-02-15
A new phase in the Rh-Cd binary system - Rh{sub 2}Cd{sub 5} has been identified and characterized by single crystal X-ray diffraction and Energy dispersive X-ray analysis. The stoichiometric compound Rh{sub 2}Cd{sub 5} crystallizes with a unit cell containing 14 atoms, in the orthorhombic space group Pbam (55). The crystal structure of Rh{sub 2}Cd{sub 5} can be described as a defect form of the In{sub 3}Pd{sub 5} structure with ordered vacancies, formed of two 2D atomic layers with the stacking sequence: ABAB. The A type layers consist of (3.6.3.6)-Kagomé nets of Cd atoms while the B type layers consist of (3{sup 5}) (3{sup 7})- nets of both Cd and Rh atoms. The stability of this line phase is investigated by first principle electronic structure calculations on the model of ordered Rh{sub 2}Cd{sub 5}. - Graphical abstract: (3.6.3.6)-Kagomé nets of cadmium atoms (top) and (3{sup 5}) (3{sup 7})- nets of both cadmium and rhodium atoms (bottom) in the structure of Rh{sub 2}Cd{sub 5}.
Single crystal structures of the new vanadates CuMgVO{sub 4} and AgMgVO{sub 4}
Energy Technology Data Exchange (ETDEWEB)
Ben Yahia, Hamdi, E-mail: Hyahia@qf.org.qa [Research Institute of Electrochemical Energy, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan); Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, PO Box 5825, Doha (Qatar); Shikano, Masahiro, E-mail: shikano.masahiro@aist.go.jp [Research Institute of Electrochemical Energy, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan); Essehli, Rachid; Belharouak, Ilias [Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, PO Box 5825, Doha (Qatar)
2016-08-01
The new compounds CuMgVO{sub 4} and AgMgVO{sub 4} have been synthesized by a solid state reaction route. Their crystal structures were determined from single-crystal X-ray diffraction data. CuMgVO{sub 4} crystallizes with Na{sub 2}CrO{sub 4}-type structure with space group Cmcm, a = 5.6932 (10), b = 8.7055 (15), c = 6.2789 (10) Å, V = 311.20 (9) Å{sup 3}, and Z = 4, whereas AgMgVO{sub 4} crystallizes in the maricite-type structure with space group Pnma, a = 9.4286 (14), b = 6.7465 (10), c = 5.3360 (8) Å, V = 339.42 (9) Å{sup 3}, and Z = 4. Both structures of CuMgVO{sub 4}, and AgMgVO{sub 4} contain MgO{sub 4} chains made up of edge-sharing MgO{sub 6} octahedra. In CuMgVO{sub 4} the MgO{sub 4} chains are interconnected through CuVO{sub 4} double chains made up of VO{sub 4} and CuO{sub 4} tetrahedra sharing corners and edges, however in AgMgVO{sub 4} the chains are interlinked by the VO{sub 4} and AgO{sub 4} tetrahedra sharing only corners. - Highlights: • We have been able to grow CuMgVO{sub 4} and AgMgVO{sub 4} single crystals. • We solved their crystal structures using single crystal data. • We compared the crystal structures of CuMgVO{sub 4} and AgMgVO{sub 4}.
Synthesis and crystal structure of the rare earth borogermanate EuGeBO{sub 5}
Energy Technology Data Exchange (ETDEWEB)
Chi, Yang; Zhuang, Yan; Guo, Sheng-Ping [Yangzhou Univ., Jiangsu (China). College of Chemistry and Chemical Engineering
2017-03-01
The synthesis and crystal structure of the rare earth borogermanate EuGeBO{sub 5} are reported. It is synthesized by high-temperature solid-state reaction and crystallizes in the monoclinic space group P2{sub 1}/c (no. 14) with the unit cell parameters a=4.8860(5), b=7.5229(8), c=9.9587(10) Aa, and β=91.709(3) . Its crystal structure features a polyanion-type layer (GeBO{sub 5}){sup 3-} constructed by BO{sub 4} and GeO{sub 4} tetrahedra connected alternatingly. Eu{sup 3+} ions are located in cavities and are coordinated by eight O atoms. Various structures of the related compounds REMM'O{sub 5} (RE=rare earth metal; M=Si, Ge, and Sn; M'=B, Al, and Ga) are also discussed.
Crystal and molecular structure of tetrathiocyanato tetrakis (triphenylphosphine oxide)uranium(IV)
Energy Technology Data Exchange (ETDEWEB)
Bombieri, G; De Paoli, G; Forsellini, E [Consiglio Nazionale delle Ricerche, Padua (Italy). Lab. di Chimica e Tecnologia dei Radioelementi; Brown, D
1979-01-01
The crystal structure of the title compound has been determined from three dimensional X-ray diffraction data. The space group and lattice parameters are given. The asymmetric unit comprises two independent U(NCS)/sub 4/(tppo)/sub 4/ molecules in each of which the coordination polyhedron around the uranium atom is close to square antiprismatic.
Method of fabricating patterned crystal structures
Yu, Liyang
2016-12-15
A method of manufacturing a patterned crystal structure for includes depositing an amorphous material. The amorphous material is modified such that a first portion of the amorphous thin-film layer has a first height/volume and a second portion of the amorphous thin-film layer has a second height/volume greater than the first portion. The amorphous material is annealed to induce crystallization, wherein crystallization is induced in the second portion first due to the greater height/volume of the second portion relative to the first portion to form patterned crystal structures.
Richmond, Craig J.; Matheu, Roc; Poater, Albert; Falivene, Laura; Benet-Buchholz, Jordi; Sala, Xavier; Cavallo, Luigi; Llobet, Antoni
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Xue, Dongxu
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Rünzi, Thomas
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wang, Haitao; Chen, Fangyi; Jia, Xiaoshi; Liu, Huimin; Ran, Xia; Ravva, Mahesh Kumar; Bai, Fu-Quan; Qu, Songnan; Li, Min; Zhang, Hong-Xing; Bré das, Jean-Luc
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wang, Haitao; Chen, Fangyi; Jia, Xiaoshi; Liu, Huimin; Ran, Xia; Ravva, Mahesh Kumar; Bai, Fu-Quan; Qu, Songnan; Li, Min; Zhang, Hong-Xing; Bré das, Jean-Luc
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Neuwald, B.; Falivene, L.; Caporaso, L.; Cavallo, Luigi; Mecking, S.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Hu, Pan; Lee, Sangsu; Seng, Herng Tun; Aratani, Naoki; Zheng, Bin; Yamada, Hiroko; Huang, Kuo-Wei; Ding, Jun; Kim, Dongho; Wu, Jishan
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Hayashi, Yukiko
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Marziale, Alexander N.
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Li, Shenyu
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Tao
2012-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zhang, Wen
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Li, Shenyu
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Marziale, Alexander N.
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Pump, Eva
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Alhilaly, Mohammad J.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zhang, Yuetao; Miyake, G.M.; John, M.G.; Falivene, L.; Caporaso, L.; Cavallo, Luigi; Chen, E.Y.-X.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zhang, Yuetao; Schmitt, Meghan; Falivene, Laura; Caporaso, Lucia; Cavallo, Luigi; Chen, Eugene Y.-X.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zhang, Yan; Kee, Choon Wee; Lee, R.; Fu, Xiao; Soh, J.Y.-T.; Loh, E.M.F.; Huang, Kuo-Wei; Tan, Choon-Hong
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Schoedel, Alexander; Wojtas, Lukasz; Kelley, Stephen P.; Rogers, Robin D.; Eddaoudi, Mohamed; Zaworotko, Michael J.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Bhatt, Prashant
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Weng, Zhiqiang
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Li, Jinling
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wang, Shuang; Zhao, Tingting; Li, Guanghua; Wojtas, L.; Huo, Qisheng; Eddaoudi, Mohamed; Liu, Yunling
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Gong, Dirong
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Analysis of phase transitions and crystal structures of novel benzothiophene derivatives
Zhang, Shuo
Although single crystal X-ray diffraction remains the most important technique for analyzing periodically ordered structures at atomic resolution, single crystal X-ray diffraction of organic macromolecules is challenged by difficulty in growing single crystals of desired size and quality. Electron crystallography of organic macromolecules, on the other hand, is limited by image resolution due to radiation damage and highly dependent on high-resolution instrumentation. Novel alkylated benzothiophene derivatives synthesized previously can be readily fabricated into semiconductor devices for various applications (photodetectors, explosive sensors, field-effect transistors, light-emitting diodes, etc.) via solution process. The object of this research is to identify phase transitions of organic macromolecules of this kind via differential scanning calorimetry and temperature-resolved wide angle X-ray diffraction, and to determine their lattice parameters and space groups by reconstruction of their reciprocal space via transmission electron microscopy/selected area electron diffraction followed by refinement with X-ray diffraction, supplemented by polarized light microscopy. Computer simulation was performed to rationalize the molecular packing schemes, so as to understand the origin of their electronic performance from crystallographic perspective.
Characterisation of a LSO scintillation crystal for space applications
Energy Technology Data Exchange (ETDEWEB)
Elftmann, Robert; Grunau, Jan; Kulkarni, Shrinivasrao; Martin, Cesar; Wimmer-Schweingruber, Robert F. [IEAP, Christian-Albrechts-Universitaet Kiel (Germany)
2013-07-01
Inorganic scintillation crystals coupled with semiconductor detectors are often used in space applications as gamma ray detectors or high energy particle calorimeters. Currently BGO (Bi{sub 4}Ge{sub 3}O{sub 12}) is widely used for this purpose because of its high stopping power, the non hygroscopy and its ruggedness, which is favorable in space applications. Cerium doped LSO (Lu{sub 2}SiO{sub 5}) offers the same benefits with higher light output capabilites and a shorter decay time. In this work a cerium doped LSO scintillation crystal coupled with a photo diode is investigated. The light yield and resolution studies for two different radioactive sources, {sup 207}Bi and {sup 60}Co, are presented. To increase the light collection and consequently the energy resolution, scintillation crystals are wrapped in highly reflective material. The increase in light collection depending on the amount of layers for the LSO crystal along with investigations of quenching effects with alpha particles and the background spectrum, which arises from radioactive cerium isotopes, are also included in this work.
Crystal structure of (E)-3-fluoro-N-((5-nitrothiophen-2-yl)methylene)aniline
Energy Technology Data Exchange (ETDEWEB)
Karataş, Şadiye; Tanak, Hasan, E-mail: hasantanak@gmail.com [Amasya University, Department of Physics, Faculty of Arts and Sciences (Turkey); Ağar, Ayşen Alaman [Ondokuz Mayıs University, Department of Chemistry, Faculty of Arts and Sciences (Turkey)
2016-05-15
The structure of the title compound C{sub 11}H{sub 7}FN{sub 2}O{sub 2}S was characterized by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P2{sub 1}/n with Z = 12, i.e. with three molecules in asymmetric unit. The molecules are not planar: the dihedral angles between the planes of thiophene and the benzene rings are 42.3(3)°, 42.0(3)°, and 48.9(2)°. In the crystal, intermolecular C–H···F interactions link the molecules through R{sub 2}{sup 2} (14) ring motif. The crystal packing is also stabilized by π···π interactions.
Syntheses, Crystal Structures and Bioactivities of Two Novel Isatin Derivatives
Institute of Scientific and Technical Information of China (English)
SHANG Jian-li; LI Hui-dong; SHANG Jun; SONG Hai-bin; LI Zheng-ming; WANG Jian-guo
2011-01-01
Two novel compoundsl-(4-fluorobenzyl)-4-chloro-(Z)-3-benzoylhydrazono-2-indolinone(1) and 1-(4-methoxybenzyl)-(Z)-3-benzoylhydrazono-2-indolinone(2) were synthesized and their crystal structures were determined by single-crystal X-ray diffraction.Compound 1(C22H15ClFN3O2) crystallized in the triclinic system,space group P1- with a=0.94198(19) nm,b=1.4339(3) nm,c=1.5018(3) nm,a=101.58(3)°,β=102.96(3)°,γ=102.73°,V=1.8602(6) nm3,Mr=407.82,Dc=1.456 g/cm3,μ=0.240 mm-1,F(000)=840,Z=4,R1=0.0442 and wR2=0.1064.Compound 2(C23H19N3O3) crystallized in the triclinic system,space group P1- with a=1.0022(2) nm,b=1.0192(2) nm,c=1.0461(2) nm,a=99.86(3)°,β=117.30(3)°,γ=94.13(3)°,V=0.9215(3) nm3,Mr=385.41,Dc=1.389 g/cm3,μ=0.094mm-1,F(000)=404,Z=2,R1=0.0403 and wR2=0.1142.The preliminary herbicidal activities of the two compounds were also evaluated.
Crystal and molecular structure of dichlorodioxobis (triphenylphosphine oxide)uranium(VI)
Energy Technology Data Exchange (ETDEWEB)
Bombieri, G; Forsellini, E [Consiglio Nazionale delle Ricerche, Padua (Italy). Lab. di Chimica e Tecnologia dei Radioelementi; Day, J P; Azeez, W I
1978-01-01
The crystal structure of (UO/sub 2/Cl/sub 2/(PPh/sub 3/O)/sub 2/) has been determined from three-dimensional X-ray diffraction data. Crystals are triclinic, space group P1, with a = 10.0101(6), b = 10.2589(9), c = 9.2347(8) A, ..cap alpha.. = 110.093(6). ..beta.. = 92.129(6), and ..gamma.. = 78.384(6), and Z = 1. The structure has been solved by the heavy-atom method from counter data, and refined by least squares to a final R of 0.054. The coordination polyhedron around uranium is a distorted octahedron, with a linear uranyl group (U-O 1.764A) perpendicular to a plane in which the two chloride and two oxide ions trans to each other occupy the corners of a rectangle (U-O 2.300; U-Cl 2.645 A).
Synthesis and crystal structure of chromium-bearing anhydrous wadsleyite
Sirotkina, E. A.; Bindi, L.; Bobrov, A. V.; Aksenov, S. M.; Irifune, T.
2018-04-01
A chromium-bearing wadsleyite (Cr- Wad) was synthesized in the model system Mg2SiO4-MgCr2O4 at 14 GPa and 1600 °C and studied from the chemical and structural point of views. Microprobe data gave the formula Mg1.930Cr0.120Si0.945O4, on the basis of 4 oxygen atoms. The crystal structure has been studied by single-crystal X-ray diffraction. The orthorhombic unit-cell parameters are: a = 5.6909(5) Å, b = 11.4640(10) Å, c = 8.2406(9) Å, V = 537.62(9) Å3, Z = 8. The structure, space group Imma, was refined to R 1 = 5.99% in anisotropic approximation using 1135 reflections with F o > 4σ( F o) and 43 parameters. Chromium was found to substitute for both Mg at the octahedral sites and Si at the tetrahedral site, according to the reaction VIMg2+ + IVSi4+ = VICr3+ + IVCr3+. On the whole, the structural topology is nearly identical to that of pure wadsleyite. The successful synthesis of Cr- Wad may be important for the thermobarometry of mantle phase associations.
International Nuclear Information System (INIS)
Clemons, William M. Jr.; Brodersen, Ditlev E.; McCutcheonn, John P.; May, Joanna L.C.; Carter, Andrew P.; Morgan-Warren, Robert J.; Wimberly, Brian T.; Ramakrishnan, Venki
2001-01-01
We describe the crystallization and structure determination of the 30 S ribosomal subunit from Thermus thermophilus. Previous reports of crystals that diffracted to 10 (angstrom) resolution were used as a starting point to improve the quality of the diffraction. Eventually, ideas such as the addition of substrates or factors to eliminate conformational heterogeneity proved less important than attention to detail in yielding crystals that diffracted beyond 3 (angstrom) resolution. Despite improvements in technology and methodology in the last decade, the structure determination of the 30 S subunit presented some very challenging technical problems because of the size of the asymmetric unit, crystal variability and sensitivity to radiation damage. Some steps that were useful for determination of the atomic structure were: the use of anomalous scattering from the LIII edges of osmium and lutetium to obtain the necessary phasing signal; the use of tunable, third-generation synchrotron sources to obtain data of reasonable quality at high resolution; collection of derivative data precisely about a mirror plane to preserve small anomalous differences between Bijvoet mates despite extensive radiation damage and multi-crystal scaling; the pre-screening of crystals to ensure quality, isomorphism and the efficient use of scarce third-generation synchrotron time; pre-incubation of crystals in cobalt hexaammine to ensure isomorphism with other derivatives; and finally, the placement of proteins whose structures had been previously solved in isolation, in conjunction with biochemical data on protein-RNA interactions, to map out the architecture of the 30 S subunit prior to the construction of a detailed atomic-resolution model.
Crystal structure of di-( N-methylmorpholine betaine)- L(+)-tartrate
Dega-Szafran, Z.; Dutkiewicz, G.; Kosturkiewicz, Z.; Szafran, M.
2002-11-01
The crystal structure of di-( N-methylmorpholine betaine)- L(+)-tartrate has been determined by X-ray diffraction method. Crystals are orthorhombic, space group P2 12 12 1, a=9.580(1), b=12.208(1), c=18.677(1) Å, Z=4, R=0.037. The molecule of L(+)-tartaric acid appears in the extended form with the hydroxyl groups as well as carboxyl groups in anti positions. The molecule is involved in a number of the intra- and intermolecular hydrogen bonds. The COOH groups of the tartaric acid link two non-equivalent N-methylmorpholine betaine molecules by a short, intermolecular O-H⋯O bonds of the lengths 2.456(1) and 2.510(1) Å. The OH groups form two different bifurcated hydrogen bonds, the intramolecular with the CO oxygen atoms (2.641(2) and 2.638(2) Å) and the intermolecular (2.919(2) and 3.084(2) Å) with neighbouring tartaric acid molecules, and link complexes in the zigzag ribbon parallel to the x-axis. The morpholine rings of both betaine molecules are in chair conformation with methyl groups in an axial position and CH 2COO - substituents in an equatorial one. In the crystals and the PM3-optimized structures there is no symmetry, both in the tartrate and N-methylmorpholine betaine moieties. FTIR spectrum confirms the complex structure of the investigated molecule.
The crystal structure and twinning of neodymium gallium perovskite single crystals
International Nuclear Information System (INIS)
Ubizskii, S.B.; Vasylechko, L.O.; Savytskii, D.I.; Matkovskii, A.O.; Syvorotka, I.M.
1994-01-01
By means of X-ray structure analysis, the crystal structure of neodymium gallium perovskite (NGP) single crystals (NdGaO 3 ) being used as a substrate for HTSC film epitaxy has been refined and the position of atoms has been determined. The possibility of YBa 2 Cu 3 O 7-x film epitaxy on the plane (110) of NGP crystal as well as its advantages and pitfalls are analysed from structural data. The twinning types in the NGP crystal were established. The twinning structure of NGP substrates is found to be stable up to a temperature of 1173 K, as differentiated from the LaGaO 3 and LaAlO 3 substrates. It is intimated that the twinning in the NGP substrates oriented as (001) can result in creation of 90 degrees twin bonds in a film, and in the case of (110)-oriented plates it is possible to ignore the twinning presence in substrate completely. (author)
Crystal structure of a Zn-doped derivative of the Li17Ge4 compound
International Nuclear Information System (INIS)
Lacroix-Orio, L.; Tillard, M.; Belin, C.
2008-01-01
The compound Li 17-ε Zn ε Ge 4 has been obtained as a side product during the preparation of the intermetallic compound Li 8 Zn 2 Ge 3 from the elements. Its structure has been determined from single crystal X-ray diffraction intensities measured at 173 K. It crystallizes in the cubic system, F4-bar3m space group, a = 18.842(1) A, Z = 20. Its crystal structure is slightly different from those so far reported in the literature for the Zn-free phase Li 17 Ge 4 , particularly concerned are the positions and the site occupations of Li atoms. Most likely, these structural variations result from the presence of a small Zn concentration in the compound. The Zn doping atom has been found only at the specific Li 4d site (about 3 at.% Zn)
Alignment structures in ferroelectric liquid crystals
Energy Technology Data Exchange (ETDEWEB)
Islam, N.U
1998-07-01
Although for many years liquid crystals were of purely scientific interest, they have now become ubiquitous in everyday life. The use of the nematic liquid crystal phase in flat panel display applications has been the main factor in this popularity. However, with the advent of the SuperTwist Nematic (STN) device, the limits to which this phase could be exploited for display applications was perhaps reached. With the discovery by Clark et al. of the Surface Stabilised Ferroelectric Liquid Crystal (SSFLC) configuration, the possibility arose of using chiral smectic liquid crystals to create large area, passively addressed, fast switching, flat panel displays. Unfortunately, the structures that form within smectic liquid crystals, and the dynamics of the switching within these, are still not fully understood. In this thesis we address the former of these, making a detailed the study of the structures that form within tilted smectic liquid crystal devices. We present here the first complete theoretical and experimental study of various different ferroelectric liquid crystal materials, where we employed theoretical models based on a simple set of assumptions to understand the behaviour of a set of increasingly complex experimental systems. We started with the simplest of these, Freely Suspended Smectic Films (FSSFs) and then worked with progressively more realistic systems in the form of homeotropically, and later, homogeneously aligned liquid crystal cells. The equilibrium structures that form get particularly complex in the last case, taking the form of tilted and chevron layering structures. In each of these cases, the predictions of the modelling are compared with our experimental results. Further, we present here the first model of the chevron cusp that seeks to include the effects of biaxiality in the S{sub C} phase. We also present a model that seeks to analyse the stability of the chevron layering structure and its relationship with tilted layers. This includes
Alignment structures in ferroelectric liquid crystals
International Nuclear Information System (INIS)
Islam, N.U.
1998-01-01
Although for many years liquid crystals were of purely scientific interest, they have now become ubiquitous in everyday life. The use of the nematic liquid crystal phase in flat panel display applications has been the main factor in this popularity. However, with the advent of the SuperTwist Nematic (STN) device, the limits to which this phase could be exploited for display applications was perhaps reached. With the discovery by Clark et al. of the Surface Stabilised Ferroelectric Liquid Crystal (SSFLC) configuration, the possibility arose of using chiral smectic liquid crystals to create large area, passively addressed, fast switching, flat panel displays. Unfortunately, the structures that form within smectic liquid crystals, and the dynamics of the switching within these, are still not fully understood. In this thesis we address the former of these, making a detailed the study of the structures that form within tilted smectic liquid crystal devices. We present here the first complete theoretical and experimental study of various different ferroelectric liquid crystal materials, where we employed theoretical models based on a simple set of assumptions to understand the behaviour of a set of increasingly complex experimental systems. We started with the simplest of these, Freely Suspended Smectic Films (FSSFs) and then worked with progressively more realistic systems in the form of homeotropically, and later, homogeneously aligned liquid crystal cells. The equilibrium structures that form get particularly complex in the last case, taking the form of tilted and chevron layering structures. In each of these cases, the predictions of the modelling are compared with our experimental results. Further, we present here the first model of the chevron cusp that seeks to include the effects of biaxiality in the S C phase. We also present a model that seeks to analyse the stability of the chevron layering structure and its relationship with tilted layers. This includes an
Structure of a new crystal form of human Hsp70 ATPase domain.
Osipiuk, J; Walsh, M A; Freeman, B C; Morimoto, R I; Joachimiak, A
1999-05-01
Hsp70 proteins are highly conserved proteins induced by heat shock and other stress conditions. An ATP-binding domain of human Hsp70 protein has been crystallized in two major morphological forms at pH 7.0 in the presence of PEG 8000 and CaCl2. Both crystal forms belong to the orthorhombic space group P212121, but show no resemblance in unit-cell parameters. Analysis of the crystal structures for both forms shows a 1-2 A shift of one of the subdomains of the protein. This conformational change could reflect a 'natural' flexibility of the protein which might be relevant to ATP binding and may facilitate the interaction of other proteins with Hsp70 protein.
Allouchi, H; Céolin, R; Berthon, L; Tombret, F; Rietveld, I B
2014-07-01
The crystal structure of L-ornithinium α-ketoglutarate (C5H13N2O2, C5H5O5) has been solved by direct methods using single crystal X-ray diffraction data. It crystallizes in the monoclinic system, space group P21, unit cell parameters a=15.4326(3), b=5.2015(1), c=16.2067(3) Å and β=91.986(1)°, containing two independent pairs of molecular ions in the asymmetric unit. An extensive hydrogen-bond network and electrostatic charges due to proton transfer provide an important part of the cohesive energy of the crystal. The conformational versatility of L-ornithine and α-ketoglutaric acid is illustrated by the present results and crystal structures available from the Cambridge Structural Database. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Neuwald, Boris; Caporaso, Lucia; Cavallo, Luigi; Mecking, Stefan
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Pump, Eva
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Sipos, Gellért
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Vummaleti, Sai V. C.; Nelson, David J.; Poater, Albert; Gó mez-Suá rez, Adriá n; Cordes, David B.; Slawin, Alexandra M. Z.; Nolan, Steven P.; Cavallo, Luigi
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Guo, Hao; Xing, Fen; Du, Guang-Fen; Huang, Kuo-Wei; Dai, Bin; He, Lin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Kuhn, Paul-Steffen; Cremer, Laura; Gavriluta, Anatolie; Jovanović, Katarina K.; Filipović, Lana; Hummer, Alfred A.; Bü chel, Gabriel E.; Dojčinović, Biljana P.; Meier, Samuel M.; Rompel, Annette; Radulović, Siniša; Tommasino, Jean Bernard; Luneau, Dominique; Arion, Vladimir B.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Vummaleti, Sai V. C.; Nelson, David J.; Poater, Albert; Gó mez-Suá rez, Adriá n; Cordes, David B.; Slawin, Alexandra M. Z.; Nolan, Steven P.; Cavallo, Luigi
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Neuwald, B.; Falivene, L.; Caporaso, L.; Cavallo, Luigi; Mecking, S.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Hayashi, Yukiko
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Tao
2012-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Lou, Xin-Hua
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Zhijie
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Savage, Mathew; da Silva, Ivan; Johnson, Mark; Carter, Joseph H.; Newby, Ruth; Suetin, Mikhail; Besley, Elena; Manuel, Pascal; Rudić, Svemir; Fitch, Andrew N.; Murray, Claire; David, William I. F.; Yang, Sihai; Schrö der, Martin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Savage, Mathew; da Silva, Ivan; Johnson, Mark; Carter, Joseph H.; Newby, Ruth; Suetin, Mikhail; Besley, Elena; Manuel, Pascal; Rudić, Svemir; Fitch, Andrew N.; Murray, Claire; David, William I. F.; Yang, Sihai; Schrö der, Martin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Savage, Mathew; da Silva, Ivan; Johnson, Mark; Carter, Joseph H.; Newby, Ruth; Suetin, Mikhail; Besley, Elena; Manuel, Pascal; Rudić, Svemir; Fitch, Andrew N.; Murray, Claire; David, William I. F.; Yang, Sihai; Schrö der, Martin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Savage, Mathew; da Silva, Ivan; Johnson, Mark; Carter, Joseph H.; Newby, Ruth; Suetin, Mikhail; Besley, Elena; Manuel, Pascal; Rudić, Svemir; Fitch, Andrew N.; Murray, Claire; David, William I. F.; Yang, Sihai; Schrö der, Martin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Savage, Mathew; da Silva, Ivan; Johnson, Mark; Carter, Joseph H.; Newby, Ruth; Suetin, Mikhail; Besley, Elena; Manuel, Pascal; Rudić, Svemir; Fitch, Andrew N.; Murray, Claire; David, William I. F.; Yang, Sihai; Schrö der, Martin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Savage, Mathew; da Silva, Ivan; Johnson, Mark; Carter, Joseph H.; Newby, Ruth; Suetin, Mikhail; Besley, Elena; Manuel, Pascal; Rudić, Svemir; Fitch, Andrew N.; Murray, Claire; David, William I. F.; Yang, Sihai; Schrö der, Martin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Savage, Mathew; da Silva, Ivan; Johnson, Mark; Carter, Joseph H.; Newby, Ruth; Suetin, Mikhail; Besley, Elena; Manuel, Pascal; Rudić, Svemir; Fitch, Andrew N.; Murray, Claire; David, William I. F.; Yang, Sihai; Schrö der, Martin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Savage, Mathew; da Silva, Ivan; Johnson, Mark; Carter, Joseph H.; Newby, Ruth; Suetin, Mikhail; Besley, Elena; Manuel, Pascal; Rudić, Svemir; Fitch, Andrew N.; Murray, Claire; David, William I. F.; Yang, Sihai; Schrö der, Martin
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Nielsen, Christian B.; Ashraf, Raja Shahid; Treat, Neil D.; Schroeder, Bob C.; Donaghey, Jenny E.; White, Andrew J. P.; Stingelin, Natalie; McCulloch, Iain
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Hu, Tong-Liang; Wang, Hailong; Li, Bin; Krishna, Rajamani; Wu, Hui; Zhou, Wei; Zhao, Yunfeng; Han, Yu; Wang, Xue; Zhu, Weidong; Yao, Zizhu; Xiang, Shengchang; Chen, Banglin
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Mohapatra, Swagat K.; Fonari, Alexandr; Risko, Chad; Yesudas, Kada; Moudgil, Karttikay; Delcamp, Jared H.; Timofeeva, Tatiana V.; Bredas, Jean-Luc; Marder, Seth R.; Barlow, Stephen
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Bhatt, Prashant
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jian, Zhongbao
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jian, Zhongbao
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Imaging of THz waves in 2D photonic crystal structures embedded in a slab waveguide
International Nuclear Information System (INIS)
Peier, P; Merbold, H; Feurer, T; Pahinin, V; Nelson, K A
2010-01-01
We present space- and time-resolved simulations and measurements of single-cycle terahertz (THz) waves propagating through two-dimensional (2D) photonic crystal structures embedded in a slab waveguide. Specifically, we use a plane wave expansion technique to calculate the band structure and a time-dependent finite-element method to simulate the temporal evolution of the THz waves. Experimentally, we measure the space-time evolution of the THz waves through a coherent time-resolved imaging method. Three different structures are laser machined in LiNbO 3 crystal slabs and analyzing the transmitted as well as the reflected THz waveforms allows determination of the bandgaps. Comparing the results with the calculated band diagrams and the time-dependent simulations shows that the experiments are consistent with 3D simulations, which include the slab waveguide geometry, the birefringence of the material, and a careful analysis of the excited modes within the band diagrams.
Crystal structure and thermal stability of AgIn(MoO4)2
International Nuclear Information System (INIS)
Klevtsov, P.V.; Solodovnikov, S.F.; Perepelitsa, A.P.; Klevtsova, R.F.
1984-01-01
Tetragonal crystals of double molybdate AgIn(MoO 4 ) 2 are prepared bi crystallization from solution in Ag 2 Mo 2 O 7 melt (a=4.998, c=36.725 A, space group I4 1 , Z=6). Its crystal structure is determined (autodaffractometer ''Syntex P2 1 '', MoKsub(α)-radiation, 876 reflections, R=0.054) in which along with Mo-tetrahedrons Mo-octahedrons are present. By mutual edges latter are united into bands forming fragments of wolframite structure alonside with (In, Ag) octahedrons. In the direction of c axis wolframite fragments alternate with scheelite fragments consisting of Mo-tetrahedrons and Ag-octavertices. The crystallochemical formula of the compound is Ag(Insub(0.75)Agsub(0.25))sub(2)Mosub(2)Osub(8) [MoO 4 ]. At a temperature of about 600 deq C AgIn-molybdate transforms into modification with NaIn(MoO 4 ) 2 structure NaIn(MoO 4 ) 2 and melts at 650 deg C decomposing into In 2 (MoO 4 ) 3 solid phase and Ag 2 MoO 4 melt
International Nuclear Information System (INIS)
Bindi, Luca; Garavelli, Anna; Pinto, Daniela; Pratesi, Giovanni; Vurro, Filippo
2008-01-01
To study the temperature-dependent structural changes and to analyze the crystal chemical behavior of the halogens as a function of temperature, a crystal of the recently discovered mineral mutnovskite, ideally Pb 2 AsS 3 (I,Cl,Br), has been investigated by X-ray single-crystal diffraction methods at 300 and 110 K. At room temperature (RT) mutnovskite was confirmed to possess a centrosymmetric structure-type, space group Pnma, while at low temperature (110 K) it adopts a non-centrosymmetric orthorhombic structure-type, space group Pnm2 1 , with a=11.5394(9) A, b=6.6732(5) A, c=9.3454(7) A, V=719.64(9) A 3 and Z=2. Mutnovskite reconverts to the centrosymmetric-type upon returning to RT thus indicating that the phase transition is completely reversible in character. The refinement of the LT-structure leads to a residual factor R=0.0336 for 1827 independent observed reflections [F o >4σ(F o )] and 80 variables. The crystal structure of cooled mutnovskite is topologically identical to that observed at RT and the slight structural changes occurring during the phase transition Pnma→Pnm2 1 are mainly restricted to the coordination polyhedra around Pb. The structure solution revealed that I and Cl are ordered into two specific sites. Indeed, the unique mixed (I,Cl) position in the RT-structure (Wyckoff position 4c) transforms into two 2a Wyckoff positions in the LT-structure hosting I and Cl, respectively. - Graphical abstract: In the crystal structure of mutnovskite at 110 K the two halogens I and Cl are ordered into two specific sites and only slight changes in the coordination environment around Pb atoms occur during the phase transition Pnma→Pnm2 1 from the RT-structure to the LT-structure. Two kinds of layers alternating along a are present in the LT-structure: Layer I contains Cl atoms and [001] columns of Pb1 and Pb4 prisms, layer II contains I atoms and [001] columns of Pb2 and Pb3 prisms
Na3Tb(PO4)2: Synthesis, crystal structure and greenish emitting properties
Zhao, Dan; Ma, Zhao; Liu, Bao-Zhong; Zhang, Rui-Juan; Wu, Zhi-Qiang; Wang, Jian; Duan, Pei-Gao
2018-03-01
A anhydrous orthoborate Na3Tb(PO4)2 has been prepared and its crystal structure was determined by X-Ray diffraction of a non-merohedral twinned single crystal. The results show that the compound crystallizes in monoclinic space group C2/c and the structure features a 3D framework containing PO4, NaO6, NaO7, NaO8 and TbO8 polyhedra. Under near-UV excitation (370 nm), Na3Tb(PO4)2 shows intense characteristic emission bands of Tb3+ (490 nm, 543 nm, 585 nm and 620 nm) with the CIE coordinate of (0.3062, 0.5901), corresponding to greenish color. The excitation spectrum covers a wide range from 340 nm to 390 nm, which indicates that phosphor Na3Tb(PO4)2 can be efficiently activated by near-UV LED ship.
International Nuclear Information System (INIS)
Batsanov, A.S.; Struchkov, Yu.T.; Lorenz, B.; Wahren, M.
1984-01-01
The title compound Tc(S 2 CNEt 2 ) 3 (Me 2 PhP) I has been prepared by the reaction of TcCl 3 (Me 2 PhP) 3 with NaS 2 CNEt 2 . The crystal structure of I has been determined by single-crystal X-ray diffraction methods at room temperature. Crystals are rhombic, space group P2 1 2 1 2 1 , with a = 8.708(1), b = 12.012(1), c = 29.626(3) A and Z = 4. The compound consists of discrete I molecules. The technetium atom has a seven-coordinated environment which is best described as a distorted pentagonal bipyramid. The Tc-P distance (2.330(3) A) is remarkably short compared with other technetium complexes with mono-dentate phosphine ligands. (author)
Synthesis, crystal structures and properties of new quinolinium derivatives
Zhang, Xinyuan; Jiang, Xingxing; Li, Yin; Lin, Zheshuai; Zhang, Guochun; Wu, Yicheng
2015-11-01
Four phenyl-substituted quinolinium salts with different counter anions, C27H27NO4S, C26H25NO5S, C25H22NO5SCl, and C25H22NO5SBr, were synthesized and their single crystals were successfully grown from methanol solution by slow evaporation. Single crystal X-ray diffraction analyses showed that C27H27NO4S crystal belongs to the noncentrosymmetric orthorhombic space group Pna21, and the other three crystals belong to centrosymmetric monoclinic space group P21/n. Their first order hyperpolarization and macroscopic nonlinearity were analyzed and physical properties were characterized by UV-vis absorption spectroscopy, and differential scanning calorimetric and thermal gravimetric analysis.
Crystal structures of superconducting sodium intercalates of hafnium nitride chloride
International Nuclear Information System (INIS)
Oro-Sole, J.; Frontera, C.; Beltran-Porter, D.; Lebedev, O.I.; Van Tendeloo, G.; Fuertes, A.
2006-01-01
Sodium intercalation compounds of HfNCl have been prepared at room temperature in naphtyl sodium solutions in tetrahydrofuran and their crystal structure has been investigated by Rietveld refinement using X-ray powder diffraction data and high-resolution electron microscopy. The structure of two intercalates with space group R3-bar m and lattice parameters a=3.58131(6)A, c=57.752(6)A, and a=3.58791(8)A, c=29.6785(17)A is reported, corresponding to the stages 2 and 1, respectively, of Na x HfNCl. For the stage 2 phase an ordered model is presented, showing two crystallographically independent [HfNCl] units with an alternation of the Hf-Hf interlayer distance along the c-axis, according with the occupation by sodium atoms of one out of two van der Waals gaps. Both stages 1 and 2 phases are superconducting with critical temperatures between 20 and 24K, they coexist in different samples with proportions depending on the synthesis conditions, and show a variation in c spacing that can be correlated with the sodium stoichiometry. High-resolution electron microscopy images of the host and intercalated samples show bending of the HfNCl bilayers as well as stacking faults in some regions, which coexist in the same crystal with ordered domains
Moessbauer determination of magnetic structure of Fe/sub 3/BO/sub 6/ crystal
Energy Technology Data Exchange (ETDEWEB)
Kovalenko, P.P.; Labushkin, V.G.; Ovsepyan, A.K.; Sarkisov, Eh.R.; Smirnov, E.V.; Prokopov, A.R.; Seleznev, V.N.
1984-10-01
The magnetic structure of a Fe/sub 3/BO/sub 6/ crystal belonging to space group Dsub(2h)sup(16)(Psub(nma)) is determined by the Moessbauer ..gamma..-radiation diffraction. The bragg reflection (700) of Moessbauer 14.4 keV ..gamma..-quanta from the Fe/sub 3/BO/sub 6/ monocrystal has been studied experimentally. A high sensitivity of the interference of ..gamma..-quantum diffraction scattering on Fe nuclei being in crystallographically non-equivalent 8d- and 4s-positions to the type of magnetic ordering in the crystal is used for determination of the magnetic structure. Agreement of the experimental results with the theoretical calculations, conducted for types of magnetic ordering resolved by the symmetry of the crystal, permitted to reliably determine the magnetic structure of this compound. The results obtained confirm the data of neutrondiffraction studies on magnetic ordering in Fe/sub 3/BO/sub 6/. Advantages of the Moessbauer-diffraction study, as compared to the magnetic neutrondiffraction method, in particular, for investigation of crystals, in which the hyperfine magnetic fields on Fe nuclei have different values, are revealed and discussed in detail.
Achari, Aniruddha; Roeber, Dana F.; Barnes, Cindy L.; Kundrot, Craig E.; Stinson, Thomas N. (Technical Monitor)
2002-01-01
Protein Crystallization Apparatus in Microgravity (PCAM) trays have been used in Shuttle missions to crystallize proteins in a microgravity environment. The crystallization experiments are 'sitting drops' similar to that in Cryschem trays, but the reservoir solution is soaked in a wick. From early 2001, crystallization experiments are conducted on the International Space Station using mission durations of months rather than two weeks on previous shuttle missions. Experiments were set up in April 2001 on Flight 6A to characterize the time crystallization experiments will take to reach equilibrium in a microgravity environment using salts, polyethylene glycols and an organic solvent as precipitants. The experiments were set up to gather data for a series of days of activation with different droplet volumes and precipitants. The experimental set up on ISS and results of this study will be presented. These results will help future users of PCAM to choose precipitants to optimize crystallization conditions for their target macromolecules for a particular mission with known mission duration. Changes in crystal morphology and size between the ground and space grown crystals of a protein and a protein -DNA complex flown on the same mission will also be presented.
Redetermination of the Crystal Structure of Al2Br6
DEFF Research Database (Denmark)
Berg, Rolf W.; Poulsen, Finn W.; Nielsen, Kurt
1997-01-01
. In accordance with previous results, the structure belongs to the monoclinic space group P2(1)/a, no. 14, C-2h(5), with a = 10.301(4), b = 7.095(2), c = 7.525(3) Angstrom, and beta = 96.44(3)degrees, and with two Al2Br6 molecules per unit cell. The single crystal was refined to R = 0.0746. Rather similar......The structure of aluminium bromide has been reinvestigated by X-ray diffraction in three different ways: (a) on a single crystal grown in a glass capillary, (b) on powder in a Debye-Scherrer glass capillary and (c) on an area of powder placed in a protective container for Bragg-Brentano geometry...... structural results were obtained from full-profile Rietveld refinements of powder data [goodness of fit = 1.38 and 2.54 for (b) and (c), respectively]. The Al2Br6 molecule consists of two edge-sharing, almost regular AlBr4 tetrahedra. The Al-Br bond distances are in the range 2.21-2.42 Angstrom...
Moosa, Basem; Fazal, A.; Ali, S.A.; Fettouhi, M.
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Pump, Eva
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Rieb, Julia; Raba, Andreas; Haslinger, Stefan; Kaspar, Manuel; Pö thig, Alexander; Cokoja, Mirza; Basset, Jean-Marie; Kü hn, Fritz E.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jian, Zhongbao
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wong, Valerie H. L.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Xue, Dongxu
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Rünzi, Thomas
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
AbdulHalim, Lina G.; Bootharaju, Megalamane Siddaramappa; Tang, Qing; Del Gobbo, Silvano; AbdulHalim, Rasha; Eddaoudi, Mohamed; Jiang, De-en; Bakr, Osman
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Liu, Yanpin; Chen, Chaohuang; Li, Huaifeng; Huang, Kuo-Wei; Tan, Jianwei; Weng, Zhiqiang
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Manzini, Simone; Nelson, David J.; Lebl, Tomas; Poater, Albert; Cavallo, Luigi; Slawin, Alexandra M. Z.; Nolan, Steven P.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Roesle, Philipp; Caporaso, Lucia; Schnitte, Manuel; Goldbach, Verena; Cavallo, Luigi; Mecking, Stefan
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Neuwald, B.; Falivene, L.; Caporaso, L.; Cavallo, Luigi; Mecking, S.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wong, Valerie H. L.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Rünzi, Thomas
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wucher, Philipp
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Tao
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Assen, Ayalew H.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Assen, Ayalew H.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Xue, Dongxu
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Dai, Gaole
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Xia, Debin
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Collado, Alba
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Collado, Alba
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Schoedel, Alexander; Wojtas, Lukasz; Kelley, Stephen P.; Rogers, Robin D.; Eddaoudi, Mohamed; Zaworotko, Michael J.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Eubank, Jarrod F.
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Dhavamurthy, M.; Peramaiyan, G.; Mohan, R.
2014-08-01
Guanidinium p-nitrophenolate (GUNP), a novel organic compound, was synthesized and crystals were grown from methanol solution by a slow evaporation solution growth technique. A single crystal X-ray diffraction study elucidated the crystal structure of GUNP belonging to the orthorhombic crystal system with space group Pnma. Thermal studies revealed that the GUNP crystal is thermally stable up to 192 °C. The lower cut-off wavelength of GUNP was found to be 505 nm by UV-vis-NIR spectral studies. The luminescence properties of the GUNP crystal were investigated. The three independent tensor coefficients ε11, ε22 and ε33 of the dielectric permittivity were calculated. The mechanical properties of the grown crystal were studied by Vickers' microhardness hardness technique.
Yamaura, Jun-Ichi; Hiroi, Zenji; Tsuda, Kenji; Izawa, Koichi; Ohishi, Yasuo; Tsutsui, Satoshi
2009-01-01
The crystal structure of the β-pyrochlore oxide superconductor KOs 2O 6 is re-examined. A single-crystal X-ray diffraction (XRD) analysis at room temperature first revealed that the compound crystallizes in a cubic structure with the centrosymmetric space group Fd3¯m, as in conventional pyrochlore oxides. Later, however, Schuck et al. claimed a different non-centrosymmetric F4¯3m structure based on their single-crystal XRD analysis. To unambiguously determine the true crystal structure of KOs 2O 6, we carried out high-resolution synchrotron powder X-ray and convergent-beam electron diffraction measurements at room temperature. The space group was determined with high reliability to be centrosymmetric Fd3¯m, not F4¯3m. This confirms the importance of the K atom location in a high-symmetry site, which causes unusually large rattling of the K atom.
Energy Technology Data Exchange (ETDEWEB)
Thiruselvam, Viswanathan [Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025 (India); Sivaraman, Padavattan [RIKEN SPring-8 Center, Harima Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Kumarevel, Thirumananseri, E-mail: kumarevel.thirumananseri@riken.jp [RIKEN SPring-8 Center, Harima Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Structural Biology Laboratory, RIKEN Yokohama Institute, RIKEN, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045 (Japan); Ponnuswamy, Mondikalipudur Nanjappagounder, E-mail: mnpsy2004@yahoo.com [Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025 (India)
2014-10-24
Highlights: • Crystal structure of ferritin was determined. • Endogenously expressed iron’s were identified. • Binuclear iron sites were observed at A and B active sites. - Abstract: Ferritin is an iron regulatory protein. It is responsible for storage and detoxification of excess iron thereby it regulates iron level in the body. Here we report the crystal structure of ferritin with two endogenously expressed Fe atoms binding in both the sites. The protein was purified and characterized by MALDI-TOF and N-terminal amino acid sequencing. The crystal belongs to I4 space group and it diffracted up to 2.5 Å. The structural analysis suggested that it crystallizes as hexamer and confirmed that it happened to be the first report of endogenously expressed Fe ions incorporated in both the A and B sites, situated in between the helices.
Crystal structure of strontium dinickel iron orthophosphate
Directory of Open Access Journals (Sweden)
Said Ouaatta
2015-10-01
Full Text Available The title compound, SrNi2Fe(PO43, synthesized by solid-state reaction, crystallizes in an ordered variant of the α-CrPO4 structure. In the asymmetric unit, two O atoms are in general positions, whereas all others atoms are in special positions of the space group Imma: the Sr cation and one P atom occupy the Wyckoff position 4e (mm2, Fe is on 4b (2/m, Ni and the other P atom are on 8g (2, one O atom is on 8h (m and the other on 8i (m. The three-dimensional framework of the crystal structure is built up by [PO4] tetrahedra, [FeO6] octahedra and [Ni2O10] dimers of edge-sharing octahedra, linked through common corners or edges. This structure comprises two types of layers stacked alternately along the [100] direction. The first layer is formed by edge-sharing octahedra ([Ni2O10] dimer linked to [PO4] tetrahedra via common edges while the second layer is built up from a strontium row followed by infinite chains of alternating [PO4] tetrahedra and FeO6 octahedra sharing apices. The layers are held together through vertices of [PO4] tetrahedra and [FeO6] octahedra, leading to the appearance of two types of tunnels parallel to the a- and b-axis directions in which the Sr cations are located. Each Sr cation is surrounded by eight O atoms.
The crystal structure of a new ternary antimonide: TmCu4-xSb2 (x 1.065)
International Nuclear Information System (INIS)
Fedyna, L.O.; Bodak, O.I.; Fedorchuk, A.O.; Tokaychuk, Ya.O.
2005-01-01
The crystal structure of the new ternary compound TmCu 4-x Sb 2 (x 1.065) was determined by direct methods from X-ray powder data (diffractometer DRON-3M, Cu Kα-radiation). It crystallizes with the orthorhombic structure type ErFe 4 Ge 2 (low-temperature modification) and is the first representative of this structure type among known antimonides: space group Pnnm, Pearson code oP14-2.13, a = 7.00565(6) A, b = 7.83582(6) A, c = 4.25051(3) A, Z = 2. Investigated structure is an orthorhombically deformed derivative of the ZrFe 4 Si 2 structure type
Shieh, H S; Ghisla, S; Hanson, L K; Ludwig, M L; Nordman, C E
1981-08-04
The molecular complex lumiflavin-2-aminobenzoic acid monohydrate (C13H12N4O2.C7H7NO2.H2O) crystallizes from from aqueous solution as red triclinic prisms. The space group is P1 with cell dimensions a = 9.660 A, b = 14.866 A, c = 7.045 A, alpha = 95.44 degrees , beta = 95.86 degrees, and gamma = 105.66 degrees . The crystal structure was solved by direct methods and refined by block-diagonal least-squares procedures to an R value of 0.050 on the basis of 1338 observed reflections. The structure is composed of stacks of alternating lumiflavin adn un-ionized (neutral) 2-aminobenzoic acid molecules. Two different modes of stacking interaction are observed. In one, 2-aminobenzoic acid overlaps all three of the isoalloxazine rings, at a mean distance of 3.36 A; in the other, 2-aminobenzoic acid interacts distance of 3.36 A; in the other, 2-aminobenzoic acid interacts with the pyrazine and dimethylbenzene moieties, at a distance of 3.42 A. Perpendicular to the stacking direction, the molecules form a continuous sheet. Each flavin is hydrogen bonded via O(2) and NH(3) to two symmetrically related aminobenzoates; the water of crystallization forms three hydrogen bonds, bridging two flavins, via O(4) and N(5), and one aminobenzoic acid. The red color of the crystals results from a charge-transfer transition involving stacked flavin and 2-aminobenzoic acid. The red color of the crystals results from a charge-transfer transition involving stacked flavin and 2-aminobenzoic acid molecules. Measurements of the polarized optical absorption spectra of crystals show that the transition moment direction for the long wavelength absorbance (beyond 530 nm) contains an out-of-plane component which can only arise from a charge-transfer interaction. Since the amino N does not make exceptionally close interactions with isoalloxazine atoms in either stacking mode (minimum interatomic distance 3.52 A), the charge transfer is presumed to involve pi orbitals of the 2-aminobenzoic acid donor.
Derivation of space groups in mm2, 222 and mmm crystal classes
International Nuclear Information System (INIS)
Nigam, G.D.
1987-08-01
An algebraic approach is developed to derive space groups using 4x4 Seitz matrices for the crystal classes mm2, 222 and mmm in the orthorhombic system. The advantage of the present method is that it is relatively simple and can be adapted to introduce space groups to beginners. One of the advantages of the present method is that it admits a geometrical visualization of the symmetry elements of space group. The method can easily be extended to other crystal classes in a straightforward way. 16 refs, 1 fig., 2 tabs
Onodera, A; Yamashita, H
2003-01-01
The crystal structure of an intermediate phase of Bi-layered ferroelectric SrBi sub 2 Ta sub 2 O sub 9 single crystals was studied by means of X-ray diffraction. An analysis of the extinction rules and X-ray intensities demonstrated that the crystal structure is orthorhombic with space group A2 sub 1 am in the ferroelectric phase and Amam in the intermediate phase; this conclusion is in good agreement with the findings of previous powder neutron diffraction studies.
International Nuclear Information System (INIS)
Terauchi, Masami; Takahashi, Mariko; Tanaka, Michiyoshi
1994-01-01
The convergent-beam electron diffraction (CBED) method for determining three-dimensional space groups is extended to the determination of the (3 + 1)-dimensional space groups for one-dimensional incommensurately modulated crystals. It is clarified than an approximate dynamical extinction line appears in the CBED discs of the reflections caused by an incommensurate modulation. The extinction enables the space-group determination of the (3 + 1)-dimensional crystals or the one-dimensional incommensurately modulated crystals. An example of the dynamical extinction line is shown using an incommensurately modulated crystal of Sr 2 Nb 2 O 7 . Tables of the dynamical extinction lines appearing in CBED patterns are given for all the (3 + 1)-dimensional space groups of the incommensurately modulated crystal. (orig.)
Selvakumar, E.; Chandramohan, A.; Anandha Babu, G.; Ramasamy, P.
2014-09-01
A new organic non-linear optical salt 3-nitroanilinium trichloroacetate has been synthesized and single crystals grown by slow solvent evaporation solution growth technique at room temperature using methanol as the solvent. The 1H and 13C Nuclear magnetic resonance spectra were recorded to establish the molecular structure of the title salt. The crystal structure of the title crystal has been determined by single crystal X-ray diffraction analysis and it belongs to monoclinic crystal system with non-centrosymmetric space group P21. Fourier transform infrared spectral study has been carried out to confirm the presence of various functional groups. The optical transmittance spectrum was recorded in the range 200-2500 nm, to find the optical transmittance window and lower cut off wavelength. The thermo gravimetric and differential thermal analyses were carried out to establish the thermal stability of the title crystal. The second harmonic generation in the title crystal was confirmed by the modified Kurtz-Perry powder test employing the Nd: YAG laser as the source for infrared radiation.
Synthesis and crystal structure of new K and Rb selenido/tellurido ferrate cluster compounds
Energy Technology Data Exchange (ETDEWEB)
Stueble, Pirmin; Berroth, Angela; Roehr, Caroline [Freiburg Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie
2016-08-01
In the course of a systematic study of alkali iron chalcogenido salts containing clusters [Fe{sub 4}Q{sub 8}] a series of new mixed-valent potassium and rubidium selenido and tellurido ferrates(II/III) was synthesized by carefully heating the pure elements enclosed in sample tubes under an argon atmosphere up to maximum temperatures of 800-900 C. Their crystal structures have been determined by means of single crystal X-ray diffraction. The mixed-valent Fe{sup II/III} tellurido ferrates A{sub 7}[Fe{sub 4}Te{sub 8}] form three different structure types. All structures contain tetramers of four edge sharing [FeTe{sub 4}] tetrahedra, which are connected by common edges to form only slightly distorted tetrahedral [Fe{sub 4}Te{sub 8}]{sup 7-} anions ('stella quadrangula') with a [Fe{sub 4}Te{sub 4}] cubane core. In all cases, these anions are surrounded by 26 alkali cations, which are located at the eight corners and the midpoints of the six faces and 12 edges of a cube. The three crystal structures can thus be described by three different packings of cuboid moieties: The monoclinic rubidium compound Rb{sub 7}[Fe{sub 4}Te{sub 8}] (space group C2/c, a = 2000.16(7), b = 897.79(3), c = 1768.12(6) pm, β = 117.4995(10) , Z = 4, R1 = 0.0296) is isotypic to the known cesium tellurido and sulfido ferrates Cs{sub 7}[Fe{sub 4}(S/Te){sub 8}]. Depending on the temperature, K{sub 7}[Fe{sub 4}Te{sub 8}] forms two different but closely related new structure types: The tetragonal r.t. modification (space group P4{sub 2}/nmc, a = 1222.25(14), c = 872.1(2) pm, Z = 2, R1 = 0.0583) crystallizes in a supergroup of the orthorhombic l.t. (100 K) form (space group Pbcn, a = 1715.5, b = 866.76(3), c = 1715.50(7) pm, Z = 4, R1 = 0.0160). In all structures, the cluster centered cubes are stacked to form columns along the short (∼ 870 pm) axis. These columns are themselves densely packed with 4 (both K compounds) and 6 (A = Rb) adjacent face-sharing columns. According to these
Optically induced structural phase transitions in ion Coulomb crystals
DEFF Research Database (Denmark)
Horak, Peter; Dantan, Aurelien Romain; Drewsen, Michael
2012-01-01
We investigate numerically the structural dynamics of ion Coulomb crystals confined in a three-dimensional harmonic trap when influenced by an additional one-dimensional optically induced periodical potential. We demonstrate that transitions between thermally excited crystal structures, such as b......We investigate numerically the structural dynamics of ion Coulomb crystals confined in a three-dimensional harmonic trap when influenced by an additional one-dimensional optically induced periodical potential. We demonstrate that transitions between thermally excited crystal structures...
Crystal structures of the free and inhibited forms of plasmepsin I (PMI) from Plasmodium falciparum.
Bhaumik, Prasenjit; Horimoto, Yasumi; Xiao, Huogen; Miura, Takuya; Hidaka, Koushi; Kiso, Yoshiaki; Wlodawer, Alexander; Yada, Rickey Y; Gustchina, Alla
2011-07-01
Plasmepsin I (PMI) is one of the four vacuolar pepsin-like proteases responsible for hemoglobin degradation by the malarial parasite Plasmodium falciparum, and the only one with no crystal structure reported to date. Due to substantial functional redundancy of these enzymes, lack of inhibition of even a single plasmepsin can defeat efforts in creating effective antiparasitic agents. We have now solved crystal structures of the recombinant PMI as apoenzyme and in complex with the potent peptidic inhibitor, KNI-10006, at the resolution of 2.4 and 3.1Å, respectively. The apoenzyme crystallized in the orthorhombic space group P2(1)2(1)2(1) with two molecules in the asymmetric unit and the structure has been refined to the final R-factor of 20.7%. The KNI-10006 bound enzyme crystallized in the tetragonal space group P4(3) with four molecules in the asymmetric unit and the structure has been refined to the final R-factor of 21.1%. In the PMI-KNI-10006 complex, the inhibitors were bound identically to all four enzyme molecules, with the opposite directionality of the main chain of KNI-10006 relative to the direction of the enzyme substrates. Such a mode of binding of inhibitors containing an allophenylnorstatine-dimethylthioproline insert in the P1-P1' positions, previously reported in a complex with PMIV, demonstrates the importance of satisfying the requirements for the proper positioning of the functional groups in the mechanism-based inhibitors towards the catalytic machinery of aspartic proteases, as opposed to binding driven solely by the specificity of the individual enzymes. A comparison of the structure of the PMI-KNI-10006 complex with the structures of other vacuolar plasmepsins identified the important differences between them and may help in the design of specific inhibitors targeting the individual enzymes. Published by Elsevier Inc.
SYNTHESIS, CHARACTERIZATION AND CRYSTAL STRUCTURE OF BIS-(2-HYDROXYBENZALDEHYDEDIAMINOGUANIZONE
Directory of Open Access Journals (Sweden)
Diana Dragancea, Vladimir B. Arion, Sergiu Shova
2008-12-01
Full Text Available The new ligand, bis(2-hydroxybenzaldehydediaminoguanizone (1 has been synthesized and characterized by elemental analysis, IR and 1H NMR spectroscopies. The crystal structure of the compound was determined by X-ray diffraction. The ligand C15H15N5O2·C2H5OH crystallizes in the monoclinic space group P21/c with unit cell parameters a = 8.9102(3, b = 10.0357(3, c = 19.7618(6 Å, β = 98.385(2°, Z = 4, V = 1748.21(9 Å3, R1 = 0.040. The amino form of the ligand adopts a planar conformation stabilized by two intramolecular hydrogen bonds of the type O–H···N, in which the H atoms of the central amino group are directed to the lone-pair regions of the azomethine nitrogen atoms.
Crystal and molecular structure of 2-thiouridine
Energy Technology Data Exchange (ETDEWEB)
Hawkinson, S W
1977-01-01
The ''minor'' nucleoside 2-thiouridine, C/sub 9/H/sub 12/O/sub 5/N/sub 2/S, crystallizes in a monoclinic cell, space group P2/sub 1/ with a = 5.049 (2), b = 7.526 (2), c = 14.050 (3) A, ..beta.. = 90.17 (2)/sup 0/, and d = 1.619 g cm/sup -3/ (for Z = 2) at 22 +- 2/sup 0/C. The structure was derived from 1334 unique intensities measured with an Oak Ridge computer-controlled diffractometer to a limit of sin theta/lambda = 0.65 A/sup -1/ with Nb-filtered Mo K..cap alpha.. radiation. Atomic parameters were obtained by a combination of Patterson and Fourier techniques and refined by full-matrix least squares to a final R(F) value of 0.023 for all data. The bond lengths and angles in the molecule agree well with those of other thiopyrimidines (C(2) - S = 1.677 A). The conformation of the sugar ring relative to the base is anti with a torsion angle chi(O(1')--C(1') ..-->.. N(1)--C(6)) of 17/sup 0/. The sugar exists in the 3'-endo conformation. The O(5')--C(5') bond is gauche to C(4) - O(1') and trans to C(4')--C(3') (torsion angles of 74 and -169/sup 0/ respectively). The molecules are linked together in the crystal by hydrogen bonds in an intricate network which is identical to that inferred by Kojic-Prodic, Liminga, Sljukic and Ruzic-Toros (Acta Cryst. (1974), B30, 1550-1555) for the crystal structure of 5,6-dihydro-2-thiouridine. 2 figures; 6 tables.
Energy Technology Data Exchange (ETDEWEB)
Bombieri, G; Benetollo, F [Consiglio Nazionale delle Ricerche, Padua (Italy). Lab. di Chimica e Tecnologia dei Radioelementi; Del Pra, A; Rojas, R
1979-01-01
The structure of the title compound, UO/sub 2/(CH/sub 2/COO)/sub 2/.H/sub 2/O, has been determined from three-dimensional X-ray data. The crystals are orthorhombic, space group Pbcn with four formula units in a cell. The coordination geometry about the uranium atom is pentagonal bipyramidal. The uranyl ions are equatorially surrounded by one water oxygen and by four carboxylate oxygen atoms of different succinic ligands. Each ligand is shared by four uranyl units giving rise to a polymeric-like structure.
What makes a crystal structure report valid?
Spek, Anthony L.|info:eu-repo/dai/nl/156517566
2018-01-01
Single crystal X-ray crystallography has developed into a unique, highly automated and accessible tool to obtain detailed information on molecular structures. Proper archival makes that referees, readers and users of the results of reported crystal structures no longer need to depend solely on the
SYNTHESIS, CHARACTERIZATION AND CRYSTAL STRUCTURES ...
African Journals Online (AJOL)
B. S. Chandravanshi
ABSTRACT. Reaction of [VO(acac)2] (acac = acetylacetonate) with ... Single crystal X-ray structural studies indicate that the hydrazone ligands coordinate to ..... Molecular structure of complex (1) at 30% probability displacement. Figure 4.
Neuwald, Boris; Caporaso, Lucia; Cavallo, Luigi; Mecking, Stefan
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Pump, Eva
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wong, Valerie H. L.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Rouen, Mathieu
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Gong, Dirong
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Lamberti, Marina; Fortman, George C.; Poater, Albert; Broggi, Julie; Slawin, Alexandra M. Z.; Cavallo, Luigi; Nolan, Steven P.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Hayashi, Yukiko; Szalda, David J.; Grills, David C.; Hanson, Jonathan C.; Huang, Kuo-Wei; Muckerman, James T.; Fujita, Etsuko
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zhang, Yuetao; Miyake, G.M.; John, M.G.; Falivene, L.; Caporaso, L.; Cavallo, Luigi; Chen, E.Y.-X.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Sun, Zhe; Lee, Sangsu; Park, Kyu Hyung; Zhu, Xiaojian; Zhang, Wenhua; Zheng, Bin; Hu, Pan; Zeng, Zebing; Das, Soumyajit; Li, Yuan; Chi, Chunyan; Li, Run-Wei; Huang, Kuo-Wei; Ding, Jun; Kim, Dongho; Wu, Jishan
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Shi, Xueliang; Burrezo, Paula Mayorga; Lee, Sangsu; Zhang, Wenhua; Zheng, Bin; Dai, Gaole; Chang, Jingjing; Navarrete, Juan T. Ló pez; Huang, Kuo-Wei; Kim, Dongho; Casado, Juan; Chi, Chunyan
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jian, Zhongbao; Falivene, Laura; Wucher, Philipp; Roesle, Philipp; Caporaso, Lucia; Cavallo, Luigi; Gö ttker-Schnetmann, Inigo; Mecking, Stefan
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zhang, Guodong; Li, Peizhou; Ding, Junfeng; Liu, Yi; Xiong, Wei-Wei; Nie, Lina; Wu, Tao; Zhao, Yanli; Tok, Alfred Iing Yoong; Zhang, Qichun
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wong, Valerie H. L.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Rünzi, Thomas
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Tao
2012-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Eubank, J.F.; Mouttaki, H.; Cairns, Amy; Belmabkhout, Youssef; Wojtas, L.; Luebke, Ryan; Al Kordi, Mohamed; Eddaoudi, Mohamed
2012-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Gao, Wen-Yang; Cai, Rong; Pham, Tony; Forrest, Katherine A.; Hogan, Adam; Nugent, Patrick; Williams, Kia; Wojtas, Lukasz; Luebke, Ryan; Weseliński, Łukasz J.; Zaworotko, Michael J.; Space, Brian; Chen, Yu-Sheng; Eddaoudi, Mohamed; XiaodongShi,; Ma, Shengqian
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Yu, Zheng-Bao
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jian, Zhongbao
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zeng, Zebing; Sung, Young Mo; Bao, Nina; Tan, Davin; Lee, Richmond; Zafra, José L.; Lee, Byung Sun; Ishida, Masatoshi; Ding, Jun; Navarrete, Juan T. Ló pez; Li, Yuan; Zeng, Wangdong; Kim, Dongho; Huang, Kuo-Wei; Webster, Richard D.; Casado, Juan; Wu, Jishan
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jothibasu, R.; Huang, Kuo-Wei; Huynh, Han Vinh
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
International Nuclear Information System (INIS)
Sen, Pinar; Yildiz, S. Zeki; Atalay, Yusuf; Dege, Necmi; Demirtas, Günes
2014-01-01
A novel 4-(2-meso-BOBIPY-phenoxy)phthalonitrile (6) derivative has been synthesized starting from BF 3 –OEt 2 complex and 4-(2-meso-dipyrromethene-phenoxy)phthalonitrile (5) which was prepared by the oxidation of 4-(2-meso-dipyrromethane-phenoxy)phthalonitrile (4). The final product exhibit noticeable spectroscopic properties which were examined by its absorption and fluorescence emission spectra. The original compounds prepared in the reaction pathway were characterized by the combination of FT-IR, 1 H and 13 C NMR, UV–vis, MS and HRMS spectral data. The final product (6) was obtained as single crystal which crystallized in the triclinic space group P-1 with a=7.9411 (6) Å, b=9.0150 (6) Å, c=14.419 (1) Å, α=74.917 (5)°, β=86.824 (6)°, γ=84.109 (5)° and Z=2. The crystal structure has intermolecular C–H···F–B and C–H···N interactions. These interactions construct bifurcated hydrogen bonds in the crystal structure. In this study, It has been calculated; molecular structure, vibrational frequencies, 1 H and 13 C NMR chemical shifts and HOMO and LUMO energies of the title compound by using B3LYP method with 6–311++G(dp) basis set, and the electronic spectral characterization was investigated for the target product, as well. - Highlights: • A novel 4-(2-meso-BOBIPY-phenoxy)phthalonitrile derivative has been synthesized. • The title product exhibit noticeable spectroscopic properties which were examined by its absorption and fluorescence emission spectra. • The final product (6) was obtained as single crystal which crystallized in the triclinic space group. • Molecular structure, vibrational frequencies, 1 H and 13 C NMR chemical shifts and HOMO and LUMO energies of the title compound were calculated theoretically. • The electronic spectral characterization was investigated, as well. • The title compound is also open to prepare further BODIPY substituted oligomeric molecules via on it
Photonic Crystal Structures with Tunable Structure Color as Colorimetric Sensors
Wang, Hui; Zhang, Ke-Qin
2013-01-01
Colorimetric sensing, which transduces environmental changes into visible color changes, provides a simple yet powerful detection mechanism that is well-suited to the development of low-cost and low-power sensors. A new approach in colorimetric sensing exploits the structural color of photonic crystals (PCs) to create environmentally-influenced color-changeable materials. PCs are composed of periodic dielectrics or metallo-dielectric nanostructures that affect the propagation of electromagnetic waves (EM) by defining the allowed and forbidden photonic bands. Simultaneously, an amazing variety of naturally occurring biological systems exhibit iridescent color due to the presence of PC structures throughout multi-dimensional space. In particular, some kinds of the structural colors in living organisms can be reversibly changed in reaction to external stimuli. Based on the lessons learned from natural photonic structures, some specific examples of PCs-based colorimetric sensors are presented in detail to demonstrate their unprecedented potential in practical applications, such as the detections of temperature, pH, ionic species, solvents, vapor, humidity, pressure and biomolecules. The combination of the nanofabrication technique, useful design methodologies inspired by biological systems and colorimetric sensing will lead to substantial developments in low-cost, miniaturized and widely deployable optical sensors. PMID:23539027
Photonic Crystal Structures with Tunable Structure Color as Colorimetric Sensors
Directory of Open Access Journals (Sweden)
Ke-Qin Zhang
2013-03-01
Full Text Available Colorimetric sensing, which transduces environmental changes into visible color changes, provides a simple yet powerful detection mechanism that is well-suited to the development of low-cost and low-power sensors. A new approach in colorimetric sensing exploits the structural color of photonic crystals (PCs to create environmentally-influenced color-changeable materials. PCs are composed of periodic dielectrics or metallo-dielectric nanostructures that affect the propagation of electromagnetic waves (EM by defining the allowed and forbidden photonic bands. Simultaneously, an amazing variety of naturally occurring biological systems exhibit iridescent color due to the presence of PC structures throughout multi-dimensional space. In particular, some kinds of the structural colors in living organisms can be reversibly changed in reaction to external stimuli. Based on the lessons learned from natural photonic structures, some specific examples of PCs-based colorimetric sensors are presented in detail to demonstrate their unprecedented potential in practical applications, such as the detections of temperature, pH, ionic species, solvents, vapor, humidity, pressure and biomolecules. The combination of the nanofabrication technique, useful design methodologies inspired by biological systems and colorimetric sensing will lead to substantial developments in low-cost, miniaturized and widely deployable optical sensors.
Crystal structure from one-electron theory
DEFF Research Database (Denmark)
Skriver, H. L.
1985-01-01
The authors have studied the crystal structure of all the 3d, 4d, and 5d transition metals at zero pressure and temperature by means of the linear muffin-tin orbital method and Andersen's force theorem. They find that, although the structural energy differences seem to be overestimated by the the......The authors have studied the crystal structure of all the 3d, 4d, and 5d transition metals at zero pressure and temperature by means of the linear muffin-tin orbital method and Andersen's force theorem. They find that, although the structural energy differences seem to be overestimated...
Directory of Open Access Journals (Sweden)
Lee Brooks
2015-09-01
Full Text Available The crystal structures of eight mono-methyl alkanes have been determined from single-crystal or high-resolution powder X-ray diffraction using synchrotron radiation. Mono-methyl alkanes can be found on the cuticles of insects and are believed to act as recognition pheromones in some social species, e.g. ants, wasps etc. The molecules were synthesized as pure S enantiomers and are (S-9-methylpentacosane, C26H54; (S-9-methylheptacosane and (S-11-methylheptacosane, C28H58; (S-7-methylnonacosane, (S-9-methylnonacosane, (S-11-methylnonacosane and (S-13-methylnonacosane, C30H62; and (S-9-methylhentriacontane, C32H66. All crystallize in space group P21. Depending on the position of the methyl group on the carbon chain, two packing schemes are observed, in which the molecules pack together hexagonally as linear rods with terminal and side methyl groups clustering to form distinct motifs. Carbon-chain torsion angles deviate by less than 10° from the fully extended conformation, but with one packing form showing greater curvature than the other near the position of the methyl side group. The crystal structures are optimized by dispersion-corrected DFT calculations, because of the difficulties in refining accurate structural parameters from powder diffraction data from relatively poorly crystalline materials.
Synthesis and crystal structure of the quaternary compound AgFe{sub 2}GaTe{sub 4}
Energy Technology Data Exchange (ETDEWEB)
Delgado, Gerzon E., E-mail: gerzon@ula.ve [Laboratorio de Cristalografía, Departamento de Química, Facultad de Ciencias, Universidad de Los Andes, Mérida 5101 (Venezuela, Bolivarian Republic of); Quintero, Eugenio; Tovar, Rafael; Grima-Gallardo, Pedro; Quintero, Miguel [Centro de Estudio de Semiconductores, Departamento de Física, Facultad de Ciencias, Universidad de Los Andes, Mérida 5101 (Venezuela, Bolivarian Republic of)
2014-11-15
Highlights: • New quaternary compound. • Synthesis from solid state reaction. • Crystal structure. • Rietveld refinement. - Abstract: The crystal structure of the quaternary compound AgFe{sub 2}GaTe{sub 4}, belonging to the system I–II{sub 2}–III–VI{sub 4}, was characterized by Rietveld refinement using X-ray powder diffraction data. The powder pattern was composed by 84.5% of the principal phase AgFe{sub 2}GaTe{sub 4} and 15.5% of the secondary phase FeTe. This material crystallizes with stannite structure in the tetragonal space group I-42m (N° 121), Z = 2, unit cell parameters a = 6.3409(2) Å, c = 12.0233(4) Å, V = 483.42(3) Å{sup 3}, and is isostructural with CuFe{sub 2}InSe{sub 4}.
Crystal structure determination and thermal behavior upon melting of p-synephrine
Energy Technology Data Exchange (ETDEWEB)
Rosa, Frédéric [Unité de Technologies Chimiques et Biologiques pour la Santé, U1022 INSERM, UMR8258 CNRS, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris Descartes, Sorbonne Paris Cité, 4 Avenue de l' Observatoire, 75006 Paris (France); Négrier, Philippe [Laboratoire Ondes et Matière d' Aquitaine, Université de Bordeaux, UMR CNRS 5798, 351 cours de la Libération, 33 405 Talence Cedex (France); Corvis, Yohann [Unité de Technologies Chimiques et Biologiques pour la Santé, U1022 INSERM, UMR8258 CNRS, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris Descartes, Sorbonne Paris Cité, 4 Avenue de l' Observatoire, 75006 Paris (France); Espeau, Philippe, E-mail: philippe.espeau@parisdescartes.fr [Unité de Technologies Chimiques et Biologiques pour la Santé, U1022 INSERM, UMR8258 CNRS, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris Descartes, Sorbonne Paris Cité, 4 Avenue de l' Observatoire, 75006 Paris (France)
2016-05-20
Highlights: • The refinement of the crystal structure is achieved from X-ray powder diffraction. • P-Synephrine is revealed to be a racemic compound. • Degradation during melting can be bypassed using high DSC scan rates. • The temperature and enthalpy of melting are then proposed for this compound. - Abstract: The crystal structure of p-synephrine was solved from a high-resolution X-ray powder diffraction pattern optimized by energy-minimization calculations using the Dreiding force field. The title compound crystallizes in a monoclinic system (space group P2{sub 1}/c, Z = 4, with a = 8.8504(11) Å, b = 12.1166(15) Å, c = 9.7820(11) Å, β = 122.551(2)°, V = 884.21(19) Å{sup 3} and d = 1.256 g cm{sup −3}). Since p-synephrine degrades upon melting, its melting data were determined from DSC experiments carried out as a function of the heating rate. This method allowed determining a melting temperature and enthalpy equal to 199.8 ± 1.3 °C and 57 ± 3 kJ mol{sup −1}, respectively.
SYNTHESIS, CHARACTERIZATION AND CRYSTAL STRUCTURE ...
African Journals Online (AJOL)
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Reaction of [MoO2(acac)2] (where acac = acetylacetonate) with N'-(2-hydroxy-4- ... Single crystal X-ray structural studies indicate that the hydrazone ligand coordinates .... Molecular structure of the complex at 30% probability displacement.
Crystal structure refinement with SHELXL
Energy Technology Data Exchange (ETDEWEB)
Sheldrick, George M., E-mail: gsheldr@shelx.uni-ac.gwdg.de [Department of Structural Chemistry, Georg-August Universität Göttingen, Tammannstraße 4, Göttingen 37077 (Germany)
2015-01-01
New features added to the refinement program SHELXL since 2008 are described and explained. The improvements in the crystal structure refinement program SHELXL have been closely coupled with the development and increasing importance of the CIF (Crystallographic Information Framework) format for validating and archiving crystal structures. An important simplification is that now only one file in CIF format (for convenience, referred to simply as ‘a CIF’) containing embedded reflection data and SHELXL instructions is needed for a complete structure archive; the program SHREDCIF can be used to extract the .hkl and .ins files required for further refinement with SHELXL. Recent developments in SHELXL facilitate refinement against neutron diffraction data, the treatment of H atoms, the determination of absolute structure, the input of partial structure factors and the refinement of twinned and disordered structures. SHELXL is available free to academics for the Windows, Linux and Mac OS X operating systems, and is particularly suitable for multiple-core processors.
Two-dimensional photonic crystal accelerator structures
Directory of Open Access Journals (Sweden)
Benjamin M. Cowan
2003-10-01
Full Text Available Photonic crystals provide a method of confining a synchronous speed-of-light mode in an all-dielectric structure, likely a necessary feature in any optical accelerator. We explore computationally a class of photonic crystal structures with translational symmetry in a direction transverse to the electron beam. We demonstrate synchronous waveguide modes and discuss relevant parameters of such modes. We then explore how accelerator parameters vary as the geometry of the structure is changed and consider trade-offs inherent in the design of an accelerator of this type.
International Nuclear Information System (INIS)
Niewa, Rainer; Czulucki, Andreas; Schmidt, Marcus; Auffermann, Gudrun; Cichorek, Tomasz; Meven, Martin; Pedersen, Bjoern; Steglich, Frank; Kniep, Ruediger
2010-01-01
Large single crystals of ZrAs x Se y (x>y, x+y≤2, PbFCl type of structure, space group P4/nmm) were grown by Chemical Transport. Structural details were studied by single crystal neutron diffraction techniques at various temperatures. One single crystal specimen with chemical composition ZrAs 1.595(3) Se 0.393(1) was studied at ambient temperature (R1=5.10 %, wR2=13.18 %), and a second crystal with composition ZrAs 1.420(3) Se 0.560(1) was investigated at 25 K (R1=2.70%, wR2=5.70 %) and 2.3 K (R1=2.30 %, wR2=4.70 %), respectively. The chemical compositions of the crystals under investigation were determined by wavelength dispersive X-ray spectroscopy. The quantification of trace elements was carried out by Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry. According to the crystal structure refinements the crystallographic 2a site is occupied by As, together with a significant amount of vacancies. One of the 2c sites is fully occupied by As and Se (random distribution). With respect to the fractional coordinates of the atoms, the crystal structure determinations based on the data obtained at 25.0 K and 2.3 K did not show significant deviations from ambient temperature results. The temperature dependence of the displacement parameters indicates a static displacement of As on the 2a sites (located on the (0 0 1) planes) for all temperatures. No indications for any occupation of interstitial sites or the presence of vacancies on the Zr (2a) site were found. - Graphical abstract: Large single crystals of ZrAs x Se y grown by Chemical Transport to study structural details as the As-Se order scheme by single crystal neutron diffraction.
International Nuclear Information System (INIS)
Oswald, H.R.; Guenter, J.R.; Dubler, E.
1975-01-01
Single crystals of the white MoO 3 . H 2 O modification (''α-molybdic acid'') were transformed by heating to 160 0 C into perfect pseudomorphs built up from oriented MoO 3 crystallites of known structure. From the mutual orientation relationship of the unit cells of both phases involved in this topotactic reaction, as determined by X-ray photographs, a model for the so far unknown crystal structure of white MoO 3 . H 2 O could be deduced. Independently, this structure was determined by X-ray diffractometer data then: space group P anti 1, a = 7.388, b = 3.700, c = 6.673 A, α = 107.8, β = 113.6, γ = 91.2 0 , Z = 2. The structure was solved from the Patterson function and refined until R = 0.088. It is built up from isolated double chains of strongly distorted [MoO 5 (H 2 O)]-octahedra sharing two common edges with each other. This result agrees well with the model derived from topotaxy, and it becomes evident how the MoO 3 lattice is formed through corner linking of the isolated double chains after the water molecules are removed. The study of topotactic phenomena seems rather generally applicable to deduce the main features of structures involved and for better understanding of structural relationships. (U.S.)
Energy Technology Data Exchange (ETDEWEB)
Rivas, Blanca de las; Rodríguez, Héctor [Instituto de Fermentaciones Industriales, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Angulo, Iván [Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain); Muñoz, Rosario [Instituto de Fermentaciones Industriales, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Mancheño, José M., E-mail: xjosemi@iqfr.csic.es [Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain); Instituto de Fermentaciones Industriales, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain)
2007-07-01
The catabolic ornithine transcarbamylase (cOTC) from L. hilgardii has been overexpressed in E. coli, purified and crystallized under two different experimental conditions. The structure has been solved by the molecular-replacement method using the atomic coordinates of catabolic ornithine transcarbamylase from P. aeruginosa as the search model. The catabolic ornithine transcarbamylase (cOTC; EC 2.1.3.3) from the lactic acid bacteria Lactobacillus hilgardii is a key protein involved in the degradation of arginine during malolactic fermentation. cOTC containing an N-terminal His{sub 6} tag has been overexpressed in Escherichia coli, purified and crystallized under two different experimental conditions using the hanging-drop vapour-diffusion method. Crystals obtained from a solution containing 8%(w/v) PEG 4000, 75 mM sodium acetate pH 4.6 belong to the trigonal space group P321 and have unit-cell parameters a = b = 157.04, c = 79.28 Å. Conversely, crystals grown in 20%(v/v) 2-methyl-2,4-pentanediol, 7.5%(w/v) PEG 4000, 100 mM HEPES pH 7.8 belong to the monoclinic space group C2 and have unit-cell parameters a = 80.06, b = 148.90, c = 91.67 Å, β = 100.25°. Diffraction data were collected in-house to 3.00 and 2.91 Å resolution for trigonal and monoclinic crystals, respectively. The estimated Matthews coefficient for the crystal forms were 2.36 and 2.24 Å{sup 3} Da{sup −1}, respectively, corresponding to 48% and 45% solvent content. In both cases, the results are consistent with the presence of three protein subunits in the asymmetric unit. The structure of cOTC has been determined by the molecular-replacement method using the atomic coordinates of cOTC from Pseudomonas aeruginosa (PDB code) as the search model.
International Nuclear Information System (INIS)
Rivas, Blanca de las; Rodríguez, Héctor; Angulo, Iván; Muñoz, Rosario; Mancheño, José M.
2007-01-01
The catabolic ornithine transcarbamylase (cOTC) from L. hilgardii has been overexpressed in E. coli, purified and crystallized under two different experimental conditions. The structure has been solved by the molecular-replacement method using the atomic coordinates of catabolic ornithine transcarbamylase from P. aeruginosa as the search model. The catabolic ornithine transcarbamylase (cOTC; EC 2.1.3.3) from the lactic acid bacteria Lactobacillus hilgardii is a key protein involved in the degradation of arginine during malolactic fermentation. cOTC containing an N-terminal His 6 tag has been overexpressed in Escherichia coli, purified and crystallized under two different experimental conditions using the hanging-drop vapour-diffusion method. Crystals obtained from a solution containing 8%(w/v) PEG 4000, 75 mM sodium acetate pH 4.6 belong to the trigonal space group P321 and have unit-cell parameters a = b = 157.04, c = 79.28 Å. Conversely, crystals grown in 20%(v/v) 2-methyl-2,4-pentanediol, 7.5%(w/v) PEG 4000, 100 mM HEPES pH 7.8 belong to the monoclinic space group C2 and have unit-cell parameters a = 80.06, b = 148.90, c = 91.67 Å, β = 100.25°. Diffraction data were collected in-house to 3.00 and 2.91 Å resolution for trigonal and monoclinic crystals, respectively. The estimated Matthews coefficient for the crystal forms were 2.36 and 2.24 Å 3 Da −1 , respectively, corresponding to 48% and 45% solvent content. In both cases, the results are consistent with the presence of three protein subunits in the asymmetric unit. The structure of cOTC has been determined by the molecular-replacement method using the atomic coordinates of cOTC from Pseudomonas aeruginosa (PDB code) as the search model
Crystal structure of beryllium amide, Be(NH2)2
International Nuclear Information System (INIS)
Jacobs, H.
1976-01-01
The x-ray investigation of single crystals of beryllium amide led to the following results. The compound crystallizes tetragonally a = 10.170 +- 0.005 A, c = 16.137 +- 0.008 A, and c/a = 1.587. The space group is I4 1 /acd. The lattice contains 32 formula units. The positions of all atoms including hydrogen were determined. The structure of Be(NH 2 ) 2 can be described by a strongly deformed cubic closepacking of anions. The cations occupy tetrahedral interstices so that 4 Be 2+ ions form a regular tetrahedron with the shortest Be-Be distances. This causes units, which can be described by Be 4 (NH 2 ) 6 (NH 2 ) 4 / 2 whereas the outer 4 amide ions serve as bridging anions to give a threedimensional arrangement. The orientation of the amide ions is given and compared with earlier results on similar metal amides. (author)
Photonics of liquid-crystal structures: A review
Energy Technology Data Exchange (ETDEWEB)
Palto, S. P., E-mail: palto@online.ru; Blinov, L M; Barnik, M I; Lazarev, V V; Umanskii, B A; Shtykov, N M [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)
2011-07-15
The original results of studies of the electro-optical and laser effects which have been performed at the Laboratory of Liquid Crystals of the Institute of Crystallography, Russian Academy of Sciences, over the last few years are reviewed. Cholesteric liquid crystals as vivid representatives of photonic structures and their behavior in an electric field are considered in detail. The formation of higher harmonics in the periodic distribution of the director field in a helical liquid crystal structure and, correspondingly, the new (anharmonic) mode of electro-optical effects are discussed. Another group of studies is devoted to bistable light switching by an electric field in chiral nematics. Polarization diffraction gratings controlled by an electric field are also considered. The results of studies devoted to microlasers on various photonic structures with cholesteric and nematic liquid crystals are considered in detail. Particular attention is given to the new regime: leaky-mode lasing. Designs of liquid crystal light amplifiers and their polarization, field, and spectral characteristics are considered in the last section.
Energy Technology Data Exchange (ETDEWEB)
Rincke, Christine; Schmidt, Horst; Voigt, Wolfgang [Institute for Inorganic Chemistry, TU Bergakademie Freiberg (Germany)
2017-03-16
The synthesis routes of Gd(HCO{sub 3}){sub 3}.5H{sub 2}O and Ho(HCO{sub 3}){sub 3}.6H{sub 2}O, which are the only known bicarbonates of rare earth metals, were refuted and the published crystal structures were discussed. Because of the structural relationship of Ho(HCO{sub 3}){sub 3}.6H{sub 2}O to rare earth nitrate hexahydrates,[] the synthesis of holmium nitrate hydrate was considered and the crystal structure of Ho(NO{sub 3}){sub 3}.5H{sub 2}O was solved by single crystal X-ray diffraction measurements. Ho(NO{sub 3}){sub 3}.5H{sub 2}O was determined to crystallize in the triclinic space group P1 (no. 2) with a = 6.5680(14) Aa, b = 9.503(2) Aa, c = 10.462(2) Aa, α = 63.739(14) , β = 94.042(2) and γ = 76.000(16) . The crystal structure consists of isolated [Ho(H{sub 2}O){sub 4}(NO{sub 3}){sub 3}] polyhedra and non-coordinating water molecules. It is isotypic to other rare earth nitrate pentahydrates. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Abdul Halim, Racha Ghassan
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Abdul Halim, Racha Ghassan
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Gong, Dirong
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Broggi, Julie; Jurčí k, Vá clav; Songis, Olivier; Poater, Albert; Cavallo, Luigi; Slawin, Alexandra M. Z.; Cazin, Catherine S. J.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Roesle, Philipp; Caporaso, Lucia; Schnitte, Manuel; Goldbach, Verena; Cavallo, Luigi; Mecking, Stefan
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wong, Valerie H. L.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Gómez-Suárez, Adrián
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Christl, Josefine T.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Nugent, P.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Nugent, P.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Dentel, H.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chua, Ming Hui; Huang, Kuo-Wei; Xu, Jianwei; Wu, Jishan
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Guillerm, Vincent; Weseliński, Łukasz J.; Belmabkhout, Youssef; Cairns, Amy J.; D'Elia, Valerio; Wojtas, Łukasz; Adil, Karim; Eddaoudi, Mohamed
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wang, Yuan; Zheng, Bin; Pan, Yupeng; Pan, Chengling; He, Lipeng; Huang, Kuo-Wei
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Leitgeb, A.
2012-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Rouen, Mathieu
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Gong, Dirong
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Xue, Dongxu
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Xue, Dongxu
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Xue, Dongxu
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Xue, Dongxu
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Xue, Dongxu
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Dai, Gaole
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Plonka, Anna M.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Plonka, Anna M.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Plonka, Anna M.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Elsaidi, Sameh K.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Gowda, Ravikumar R.; Caporaso, Lucia; Cavallo, Luigi; Chen, Eugene Y.-X.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zeng, Wangdong; Sun, Zhe; Herng, Tun Seng; Goncalves, Theo; Gopalakrishna, Tullimilli Y.; Huang, Kuo-Wei; Ding, Jun; Wu, Jishan
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Schoedel, Alexander; Boyette, Wesley; Wojtas, Lukasz; Eddaoudi, Mohamed; Zaworotko, Michael J.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zheng, Bing; Sun, Xiaodong; Li, Guanghua; Cairns, Amy J.; Kravtsov, Victor Ch.; Huo, Qisheng; Liu, Yunling; Eddaoudi, Mohamed
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Zheng, Bing; Sun, Xiaodong; Li, Guanghua; Cairns, Amy J.; Kravtsov, Victor Ch.; Huo, Qisheng; Liu, Yunling; Eddaoudi, Mohamed
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Lou, Xin-Hua
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Ye, Qun
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Luo, Jie; Wang, Haifei; Han, Xiao; Xu, Li-Wen; Kwiatkowski, J.; Huang, Kuo-Wei; Lu, Yixin
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jothibasu, R.; Huang, Kuo-Wei; Huynh, Han Vinh
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jothibasu, R.; Huang, Kuo-Wei; Huynh, Han Vinh
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Warnan, Julien; Cabanetos, Clement; Bude, Romain; El Labban, Abdulrahman; LI, LIANG; Beaujuge, Pierre
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
International Nuclear Information System (INIS)
Liu, Yueyong; Xu, Yanhui; Zhu, Jieqing; Qiu, Bingsheng; Rao, Zihe; Gao, George F.; Tien, Po
2005-01-01
Single crystals of the central structure domains from mumps virus F protein have been obtained by the hanging-drop vapour-diffusion method. A diffraction data set has been collected to 2.2 Å resolution. Fusion of members of the Paramyxoviridae family involves two glycoproteins: the attachment protein and the fusion protein. Changes in the fusion-protein conformation were caused by binding of the attachment protein to the cellular receptor. In the membrane-fusion process, two highly conserved heptad-repeat (HR) regions, HR1 and HR2, are believed to form a stable six-helix coiled-coil bundle. However, no crystal structure has yet been determined for this state in the mumps virus (MuV, a member of the Paramyxoviridae family). In this study, a single-chain protein consisting of two HR regions connected by a flexible amino-acid linker (named 2-Helix) was expressed, purified and crystallized by the hanging-drop vapour-diffusion method. A complete X-ray data set was obtained in-house to 2.2 Å resolution from a single crystal. The crystal belongs to space group C2, with unit-cell parameters a = 161.2, b = 60.8, c = 40.1 Å, β = 98.4°. The crystal structure will help in understanding the molecular mechanism of Paramyxoviridae family membrane fusion
Synthesis, Crystal Structure of a Novel Mn Complex with Nicotinoyl-Glycine
Directory of Open Access Journals (Sweden)
Xin Wang
2016-12-01
Full Text Available A novel manganese complex, C16H26MnN4O12, was synthesized by the reaction of nicotinoyl-glycine and NaOH in an ethanol/water solution and structurally characterized by elemental analysis, UV-vis spectrum, IR spectrum and single-crystal X-ray diffraction analysis. The crystal of the complex belongs to the triclinic space group P1 with a = 7.8192(16 Å, b = 8.8800(18 Å, c = 9.0142(18 Å, α = 83.14(3°, β = 65.27(3°, γ = 81.67(3°, V = 516.3(2 Å3, Z = 1, Dx = 1.542 mg·m−3, μ = 0.66 mm−1, F(000 = 271, and final R1 = 0.0381, ωR2 = 0.0964. The nicotinoyl-glycine ligand acts as a bridging ligand to connect the manganese ions by the hydrogen interactions; thus, the complex expands into a 3D supramolecular net structure.
Li, Xiayue; Curtis, Farren S.; Rose, Timothy; Schober, Christoph; Vazquez-Mayagoitia, Alvaro; Reuter, Karsten; Oberhofer, Harald; Marom, Noa
2018-06-01
We present Genarris, a Python package that performs configuration space screening for molecular crystals of rigid molecules by random sampling with physical constraints. For fast energy evaluations, Genarris employs a Harris approximation, whereby the total density of a molecular crystal is constructed via superposition of single molecule densities. Dispersion-inclusive density functional theory is then used for the Harris density without performing a self-consistency cycle. Genarris uses machine learning for clustering, based on a relative coordinate descriptor developed specifically for molecular crystals, which is shown to be robust in identifying packing motif similarity. In addition to random structure generation, Genarris offers three workflows based on different sequences of successive clustering and selection steps: the "Rigorous" workflow is an exhaustive exploration of the potential energy landscape, the "Energy" workflow produces a set of low energy structures, and the "Diverse" workflow produces a maximally diverse set of structures. The latter is recommended for generating initial populations for genetic algorithms. Here, the implementation of Genarris is reported and its application is demonstrated for three test cases.
Comparison of multiple crystal structures with NMR data for engrailed homeodomain
Energy Technology Data Exchange (ETDEWEB)
Religa, Tomasz L. [MRC Centre for Protein Engineering (United Kingdom)], E-mail: tlr25@mrc-lmb.cam.ac.uk
2008-03-15
Two methods are currently available to solve high resolution protein structures-X-ray crystallography and nuclear magnetic resonance (NMR). Both methods usually produce highly similar structures, but small differences between both solutions are always observed. Here the raw NMR data as well as the solved NMR structure were compared to the multiple crystal structures solved for the WT 60 residue three helix bundle engrailed homeodomain (EnHD) and single point mutants. There was excellent agreement between TALOS-predicted and crystal structure-observed dihedral angles and a good agreement for the {sup 3}J(H{sup N}H{sup {alpha}}) couplings for the multiple crystal structures. Around 1% of NOEs were violated for any crystal structure, but no NOE was inconsistent with all of the crystal structures. Violations usually occurred for surface residues or for residues for which multiple discreet conformations were observed between the crystal structures. Comparison of the disorder shown in the multiple crystal structures shows little correlation with dynamics under native conditions for this protein.
Structure analysis on synthetic emerald crystals
Lee, Pei-Lun; Lee, Jiann-Shing; Huang, Eugene; Liao, Ju-Hsiou
2013-05-01
Single crystals of emerald synthesized by means of the flux method were adopted for crystallographic analyses. Emerald crystals with a wide range of Cr3+-doping content up to 3.16 wt% Cr2O3 were examined by X-ray single crystal diffraction refinement method. The crystal structures of the emerald crystals were refined to R 1 (all data) of 0.019-0.024 and w R 2 (all data) of 0.061-0.073. When Cr3+ substitutes for Al3+, the main adjustment takes place in the Al-octahedron and Be-tetrahedron. The effect of substitution of Cr3+ for Al3+ in the beryl structure results in progressively lengthening of the Al-O distance, while the length of the other bonds remains nearly unchanged. The substitution of Cr3+ for Al3+ may have caused the expansion of a axis, while keeping the c axis unchanged in the emerald lattice. As a consequence, the Al-O-Si and Al-O-Be bonding angles are found to decrease, while the angle of Si-O-Be increases as the Al-O distance increases during the Cr replacement.
SYNTHESIS, THERMAL STUDIES AND CRYSTAL STRUCTURE OF 4-AMINOPYRIDINIUM SEMI-OXALATE HEMIHYDRATE
Directory of Open Access Journals (Sweden)
CECILIA CHACÓN
2017-06-01
Full Text Available The title compound has been synthesized by grinding in an agate mortar. Its structure was characterized by TGA-DSC studies and single-crystal X-ray diffraction. This compound crystallize in the monoclinic system with space group C2/c, Z = 4, and unit cell parameters a = 16.109(2 Å, b = 5.748(7 Å, c = 20.580(3 Å, β = 107.36(1°. The salt, C2HO4-.C5H7N+.0.5 H2O, is an ionic ensemble assisted by hydrogen bonds established between 4-aminopyridinium cations, oxalate anions and water molecules. The three components thus construct a supramolecular assembly with a three-dimensional hydrogen bonded framework.
Pump, Eva
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Queval, Pierre; Jahier, Claire; Rouen, Mathieu; Artur, Isabelle; Legeay, Jean-Christophe; Falivene, Laura; Toupet, loic; Cré visy, Christophe; Cavallo, Luigi; Basle, Olivier; Mauduit, Marc
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Yao, Zizhu
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jian, Zhongbao
2017-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Shi, Xueliang
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Gong, Dirong
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Gong, Dirong
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Li, Yuan; Heng, Wee-Kuan; Lee, Byung Sun; Aratani, N.; Zafra, J.L.; Bao, N.; Lee, R.; Sung, Young Mo; Sun, Zhe; Huang, Kuo-Wei; Webster, R.D.; Navarrete, J.T.L.; Kim, Dongho; Osuka, A.; Casado, J.; Ding, Jun; Wu, Jishan
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jia, Wei-Guo
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wucher, Philipp
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Eubank, J.F.; Nouar, F.; Luebke, Ryan; Cairns, Amy; Wojtas, L.; Al Kordi, Mohamed; Bousquet, T.; Hight, M.R.; Eckert, J.; Embs, J.P.; Georgiev, P.A.; Eddaoudi, Mohamed
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wang, Yuan; Zheng, Bin; Pan, Yupeng; Pan, Chengling; He, Lipeng; Huang, Kuo-Wei
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Manzini, Simone; Poater, Albert; Nelson, David J.; Cavallo, Luigi; Slawin, Alexandra M. Z.; Nolan, Steven P.
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Vummaleti, Sai V. C.; Nelson, David J.; Poater, Albert; Gó mez-Suá rez, Adriá n; Cordes, David B.; Slawin, Alexandra M. Z.; Nolan, Steven P.; Cavallo, Luigi
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Guan, Chao; Zhang, Dan-Dan; Pan, Yupeng; Iguchi, Masayuki; Ajitha, Manjaly John; Hu, Jinsong; Li, Huaifeng; Yao, Changguang; Huang, Mei-Hui; ShixiongMin,; Zheng, Junrong; Himeda, Yuichiro; Kawanami, Hajime; Huang, Kuo-Wei
2017-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Yao, Zizhu
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wang, Yuan
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wucher, Philipp
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Chen, Tao
2015-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Rouen, Mathieu
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wong, Valerie H. L.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Hong, Miao; Tang, Xiaoyan; Falivene, Laura; Caporaso, Lucia; Cavallo, Luigi; Chen, Eugene Y.-X.
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Cairns, Amy J.; Eckert, Juergen; Wojtas, Lukasz; Thommes, Matthias; Wallacher, Dirk; Georgiev, Peter A.; Forster, Paul M.; Belmabkhout, Youssef; Ollivier, Jacques; Eddaoudi, Mohamed
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Cairns, Amy J.; Eckert, Juergen; Wojtas, Lukasz; Thommes, Matthias; Wallacher, Dirk; Georgiev, Peter A.; Forster, Paul M.; Belmabkhout, Youssef; Ollivier, Jacques; Eddaoudi, Mohamed
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Schoedel, Alexander; Wojtas, Lukasz; Kelley, Stephen P.; Rogers, Robin D.; Eddaoudi, Mohamed; Zaworotko, Michael J.
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jothibasu, R.; Huang, Kuo-Wei; Huynh, Han Vinh
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Li, Peng; He, Yabing; Zhao, Yunfeng; Weng, Linhong; Wang, Hailong; Krishna, Rajamani; Wu, Hui; Zhou, Wei; O'Keeffe, Michael; Han, Yu; Chen, Banglin
2014-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Gong, Dirong; Liu, Wen; Pan, Weijing; Chen, Tao; Jia, Xiaoyu; Huang, Kuo-Wei; Zhang, Xuequan
2016-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Jothibasu, R.; Huang, Kuo-Wei; Huynh, Han Vinh
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Wang, Shuang; Zhao, Tingting; Li, Guanghua; Wojtas, L.; Huo, Qisheng; Eddaoudi, Mohamed; Liu, Yunling
2011-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Schoedel, Alexander
2013-01-01
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
International Nuclear Information System (INIS)
Esteves, D.; Tedesco, J.C.D.; Pedro, S.S.; Cruz, C.; Reis, M.S.; Brandão, P.
2014-01-01
One novel coordination polymer [Mn 2 (μ-2,6-DCBA) 3 (μ 2 -CH 3 CO 2 ) 2 (2H 2 O)]·2H 2 O (2,6-DCBA = 2,6-dichlorobenzoato) (compound 1) has been synthesized by self-assembly of bridging ligand 2,6-dichlorobenzoic acid and manganese acetate tetrahydrate. Single crystal X-ray diffraction analysis reveals that this compound crystallizes in space group P2 1 /c with a = 10.1547(7), b = 24.5829(2), c = 12.6606(2) Å, β = 93.707(3), V = 3153.9(3) Å 3 and Z = 4. The Mn(II) ions are connected by 2,6-DCBA and acetate group in μ-bridging mode to form 1D chains. Two water molecules are in the inter-layer space forming strong hydrogen bonds originating 2D layer structure. The preparation of this compound is very sensitive to the synthesis conditions, mainly to the solution pH and solvent yielding other two compounds 2 and 3. In compound 1 Mn(II) atoms in octahedral coordination are arranged in a zig–zag chain, with a trimeric structure repeated periodically along the chain, giving two exchange parameters: J 1 related to a syn–syn bond; and J 2 related to a bond of type anti–anti. A theoretical model was developed and then fitted to the magnetic susceptibility data, revealing an antiferromagnetic arrangement along the chain
Directory of Open Access Journals (Sweden)
Mohammad Arfan
2016-01-01
Full Text Available The crystal structure of 2-amino-N′-[(1Z-1-(4-chlorophenylethylidene]benzohydrazide (I is determined by X-ray diffraction at room temperature. The structure of I also was characterized by elemental analysis, mass, FT-IR and NMR spectroscopic techniques. The compound crystallizes in triclinic system, and space group is P1¯. Unit-cell dimensions are the following: a = 7.05380(10 Å, b = 7.65490(10 Å, c = 13.7094(4 Å, V = 694.01(2 Å3, Z = 2. The title compound is nearly planar and has intermolecular N–H⋯O hydrogen bonding. According to the spectral data, I exhibits an amide-iminol tautomerism.
The crystal structure of TeCl3+AuCl4-
International Nuclear Information System (INIS)
Jones, P.G.; Jentsch, D.; Schwarzmann, E.
1986-01-01
TeCl 3 + AuCl 4 - crystallizes in the triclinic space group Panti 1 with a=7.564(2), b=7.720(3), c=8.964(3) A, α=78.26(3), β=88.84(3), γ=89.35(3) 0 , Z=2. The structure was refined to R 0.041 for 1380 reflections. The cation polyhedron, including secondary Te...Cl interactions, is a square pyramid with mean Te-Cl 2.294, Te...Cl 3.028 A. The secondary interactions link the ions to form centrosymmetric (TeCl 3 .AuCl 4 ) 2 dimers. (orig.)
Bukvetskii, B V; Mirochnik, A G; Zhikhareva, P A
2017-05-01
The atomic structure of crystals of the [Eu(NО 3 ) 3 (HMPA) 3 ] [hexamethylphosphotriamide (HMPA)] complex characterized by an intensive luminescence and triboluminescence was determined using X-ray structural analysis. Noncentrosymmetric crystals have a monoclinic syngony: a = 16.0686 (3), b = 11.0853 (2), c = 20.9655 Å (4), β = 93.232° (1), space group P2 1 , Z = 4, ρ calc = 1.560 g/cm 3 . The crystal structure is represented by individual С 18 Н 54 EuN 12 O 12 P 3 complexes linked through van der Waals interactions with clearly expressed cleavage planes. The Eu(III) atom coordination polyhedron reflected the state of a distorted square antiprism. Structural aspects of the suggested model, including formation of triboluminescence properties, were considered and the role of the cleavage planes was discussed. Copyright © 2016 John Wiley & Sons, Ltd.
Structural peculiarities and point defects of bulk-ZnO single crystals
International Nuclear Information System (INIS)
Kaurova, I.A.; Kuz’micheva, G.M.; Rybakov, V.B.; Cousson, A.; Gayvoronsky, V.Ya.
2014-01-01
Highlights: • ZnO single crystals of different color were grown by the hydrothermal method. • Point defects in ZnO have been firstly investigated by neutron diffraction. • Presence of additional reflections caused by kinetic growth effects was revealed. • The relationship between the color and zinc and oxygen vacancies was found. • Photoinduced variation of transmittance versus the CW laser intensity was analyzed. - Abstract: ZnO single crystals are related to promising direct wide band gap semiconductor materials belonging to the A II B VI type of compounds with wurtzite structure. “Unintentional” n-type conductivity in ZnO may be caused by zinc and oxygen vacancies, and interstitial zinc atoms. To date, the comprehensive structural investigation and analysis of point defects in ZnO is absent in literature. Green, light green and almost colorless ZnO single crystals grown by the hydrothermal method in concentrated alkali solutions 4M(KOH) + 1M(LiOH) + 0.1M(NH 4 OH) on monohedral seeds [0 0 0 1] at crystallization temperatures in the range of 330–350 °C and pressures in the range of 30–50 MPa have been firstly investigated by neutron diffraction. It was revealed the presence of additional reflections (∼12–∼16%) for all the crystals caused by kinetic growth effects that give grounds to assign them to the space group P3 rather than to P6 3 mc. Analysis of the refined compositions together with the color of ZnO crystals does not rule out the relationship between the color and vacancies in the zinc and oxygen positions whose concentration decreases with the discoloration of the samples. The analysis of the photoinduced variation of the total and on-axis transmittance versus the CW laser intensity showed that the colored samples have profound deep defects related to oxygen vacancies
Energy Technology Data Exchange (ETDEWEB)
Dhanaraj, P.V. [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam 603 110 (India); Rajesh, N.P., E-mail: rajeshnp@hotmail.com [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam 603 110 (India); Sundar, J. Kalyana; Natarajan, S. [Department of Physics, Madurai Kamaraj University, Madurai 625 021 (India); Vinitha, G. [Department of Physics, Crescent Engineering College, Chennai 600 048 (India)
2011-09-15
Highlights: {yields} Good quality crystals of nicotinium trifluoroacetate in monoclinic system were grown for first time. {yields} Nicotinium trifluoroacetate crystal exhibits third order nonlinear optical properties. {yields} The optical spectrum of nicotinium trifluoroacetate crystal reveals the wide transmission in the entire range with cutoff wavelength at 286 nm. {yields} Nicotinium trifluoroacetate is a low dielectric constant material. - Abstract: An organic material, nicotinium trifluoroacetate (NTF) was synthesized and single crystals in monoclinic system were grown from aqueous solution for the first time. Its solubility and metastable zone width were estimated. The crystal structure of NTF was analyzed to reveal the molecular arrangements and the formation of hydrogen bonds in the crystal. High-resolution X-ray diffraction rocking curve measurements were performed to analyze the structural perfection of the grown crystals. Functional groups in NTF were identified by Fourier transform infrared spectral analysis. Thermal behaviour and stability of NTF were studied by thermogravimetric and differential thermal analysis and differential scanning calorimetry. Mechanical and dielectric properties of NTF crystals were analyzed. Optical studies reveal that NTF crystals are transparent in the wavelength range 286-1100 nm. The third order nonlinear optical parameters of NTF were derived by the Z-scan technique.
Shvanskaya, L. V.; Yakubovich, O. V.; Koshelev, A. V.; Vasiliev, A. N.
2018-02-01
Two aluminophosphate analogues of the mineral pollucite with the general formula Cs2(M,Al)3P3O12 (where M = Cu or Mn) have been synthesized by high-temperature flux and structurally characterized using the single-crystal X-ray diffraction. Both samples crystallize in cubic I4132 space group, Z = 8, with a = 13.5911(5) and a = 13.8544(7) for Cu- and Mn-loaded phases, respectively. Their framework structures are based on the ANA-type topology and exhibit the partial ordering of the metal (M/Al) and phosphorus (P) cations over the tetrahedral sites. The regular changes in cell dimensions and volumes in the row Cs2(Cu,Al)3P3O12→Cs2(Mn,Al)3P3O12 obviously correspond to increasing radii of the transition metal. The crystal chemical analysis of both pollucite-like phases show correlations between the difference in the radii size of tetrahedral cations and the degree of distortion of flexible ANA-type framework due to decreasing of the intertetrahedral angles (T-O-T). Magnetic susceptibility measurements indicate that both compounds are paramagnets in the temperature range of 2-300 K.
Crystal structure and chemical bonding analysis of BaPtCd{sub 2}
Energy Technology Data Exchange (ETDEWEB)
Gulo, Fakhili [Department of Chemical Education, Sriwijaya University, Inderalaya 30662, South Sumatra (Indonesia); Koehler, Juergen [Max Planck Institut fuer Festkoerperforschung, Heisenbergstrasse 1, 70569 Stuttgart (Germany)
2015-03-15
The new ternary intermetallic phase, BaPtCd{sub 2}, was synthesized by solid-state reaction from direct combination of the elements in a stoichiometric mixture. The reaction was done at 850 C for 15 h, followed by an equilibration at 600 C for 4 d. The crystal structure was determined by X-ray diffraction method on a single crystal. BaPtCd{sub 2} is isotypic to MgCuAl{sub 2} and crystallizes in the orthorhombic space group Cmcm [a = 4.467(2), b = 11.143(4), c = 8.240(3) Aa, V = 410.2(3) Aa{sup 3}, and Z = 4]. Barium atoms are linked together forming zigzag chains. Cadmium atoms are bonded to each other forming six-membered rings of platinum centered boat and anti-boat conformations. BaPtCd{sub 2} contains 16 electrons per formula unit and belongs to the electron poorest compounds with MgCuAl{sub 2} type structure. Calculations based on the linear muffin-tin orbitals method in the atomic spheres approximation show that significant bonding states in BaPtCd{sub 2} are unoccupied. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Crystal growth and structure of L-methionine L-methioninium hydrogen maleate-a new NLO material
International Nuclear Information System (INIS)
Natarajan, Subramanian; Rajan Devi, Neelamagam; Britto Dhas, Sathiya Dhas Martin; Athimoolam, Shanmuganarayanan
2008-01-01
A new organic nonlinear optical (NLO) crystal from the amino acid family, viz., L-methionine L-methioninium hydrogen maleate (LMMM), has been grown by slow evaporation method from aqueous solution. Bulk crystals were grown using submerged seed solution method. The structure was elucidated using the single crystal x-ray diffraction data. The compound crystallized in the space group P2 1 and the unit cell contains a protonated L-methioninium cation and a zwitterionic methionine residue plus a maleate anion. The backbone conformation angles Ψ 1 and Ψ 2 are in cis and trans configurations for both the methionine and methioninium residues, respectively. Amino and carboxyl groups of the methioninium and methionine residues are connected through N-H...O hydrogen bonds leading to a ring R 2 2 (10) motif.
The Crystal Structures of Two Novel Cadmium-Picolinic Acid ...
African Journals Online (AJOL)
The crystal structures of two novel cadmium-picolinic acid complexes grown in aqueous solutions at selected pH values are reported. The structures are compared to expected solution species under the same conditions. The crystal structure of complex 1 exhibits a seven coordinate structure which contains a protonated ...
Band structures in fractal grading porous phononic crystals
Wang, Kai; Liu, Ying; Liang, Tianshu; Wang, Bin
2018-05-01
In this paper, a new grading porous structure is introduced based on a Sierpinski triangle routine, and wave propagation in this fractal grading porous phononic crystal is investigated. The influences of fractal hierarchy and porosity on the band structures in fractal graidng porous phononic crystals are clarified. Vibration modes of unit cell at absolute band gap edges are given to manifest formation mechanism of absolute band gaps. The results show that absolute band gaps are easy to form in fractal structures comparatively to the normal ones with the same porosity. Structures with higher fractal hierarchies benefit multiple wider absolute band gaps. This work provides useful guidance in design of fractal porous phononic crystals.
Construction of crystal structure prototype database: methods and applications.
Su, Chuanxun; Lv, Jian; Li, Quan; Wang, Hui; Zhang, Lijun; Wang, Yanchao; Ma, Yanming
2017-04-26
Crystal structure prototype data have become a useful source of information for materials discovery in the fields of crystallography, chemistry, physics, and materials science. This work reports the development of a robust and efficient method for assessing the similarity of structures on the basis of their interatomic distances. Using this method, we proposed a simple and unambiguous definition of crystal structure prototype based on hierarchical clustering theory, and constructed the crystal structure prototype database (CSPD) by filtering the known crystallographic structures in a database. With similar method, a program structure prototype analysis package (SPAP) was developed to remove similar structures in CALYPSO prediction results and extract predicted low energy structures for a separate theoretical structure database. A series of statistics describing the distribution of crystal structure prototypes in the CSPD was compiled to provide an important insight for structure prediction and high-throughput calculations. Illustrative examples of the application of the proposed database are given, including the generation of initial structures for structure prediction and determination of the prototype structure in databases. These examples demonstrate the CSPD to be a generally applicable and useful tool for materials discovery.
Construction of crystal structure prototype database: methods and applications
International Nuclear Information System (INIS)
Su, Chuanxun; Lv, Jian; Wang, Hui; Wang, Yanchao; Ma, Yanming; Li, Quan; Zhang, Lijun
2017-01-01
Crystal structure prototype data have become a useful source of information for materials discovery in the fields of crystallography, chemistry, physics, and materials science. This work reports the development of a robust and efficient method for assessing the similarity of structures on the basis of their interatomic distances. Using this method, we proposed a simple and unambiguous definition of crystal structure prototype based on hierarchical clustering theory, and constructed the crystal structure prototype database (CSPD) by filtering the known crystallographic structures in a database. With similar method, a program structure prototype analysis package (SPAP) was developed to remove similar structures in CALYPSO prediction results and extract predicted low energy structures for a separate theoretical structure database. A series of statistics describing the distribution of crystal structure prototypes in the CSPD was compiled to provide an important insight for structure prediction and high-throughput calculations. Illustrative examples of the application of the proposed database are given, including the generation of initial structures for structure prediction and determination of the prototype structure in databases. These examples demonstrate the CSPD to be a generally applicable and useful tool for materials discovery. (paper)
Crystallization and preliminary X-ray structural studies of a Melan-A pMHC–TCR complex
International Nuclear Information System (INIS)
Yuan, Fang; Georgiou, Theonie; Hillon, Theresa; Gostick, Emma; Price, David A.; Sewell, Andrew K.; Moysey, Ruth; Gavarret, Jessie; Vuidepot, Annelise; Sami, Malkit; Bell, John I.; Gao, George F.; Rizkallah, Pierre J.; Jakobsen, Bent K.
2007-01-01
A preliminary X-ray crystal structural study of a soluble cognate T-cell receptor (TCR) in complex with a pMHC presenting the Melan-A peptide (ELAGIGILTV) is reported. The TCR and pMHC were refolded, purified and mixed together to form complexes, which were crystallized using the sitting-drop vapour-diffusion method. Single TCR–pMHC complex crystals were cryocooled and used for data collection. Melanocytes are specialized pigmented cells that are found in all healthy skin tissue. In certain individuals, diseased melanocytes can form malignant tumours, melanomas, which cause the majority of skin-cancer-related deaths. The melanoma-associated antigenic peptides are presented on cell surfaces via the class I major histocompatibility complex (MHC). Among the melanoma-associated antigens, the melanoma self-antigen A/melanoma antigen recognized by T cells (Melan-A/MART-1) has attracted attention because of its wide expression in primary and metastatic melanomas. Here, a preliminary X-ray crystal structural study of a soluble cognate T-cell receptor (TCR) in complex with a pMHC presenting the Melan-A peptide (ELAGIGILTV) is reported. The TCR and pMHC were refolded, purified and mixed together to form complexes, which were crystallized using the sitting-drop vapour-diffusion method. Single TCR–pMHC complex crystals were cryocooled and used for data collection. Diffraction data showed that these crystals belonged to space group P4 1 /P4 3 , with unit-cell parameters a = b = 120.4, c = 81.6 Å. A complete data set was collected to 3.1 Å and the structure is currently being analysed