Synthesis and Study of Electrical Properties of SbTeI

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Harish K. Dubey

2014-01-01

Full Text Available Needle shaped SbTeI crystals were obtained by solid state reaction. Electrical resistance was measured in the temperature range of 4 K to 550 K. SbTeI shows a metallic behavior from 4 K to 300 K, and at higher temperature (>300 K, it shows semiconducting behavior. Unlike SbSI, this material shows almost zero resistance around 550 K. It shows a piezoelectric behavior with a capacitance of 717 pF and its carrier density and nobilities are found to be 2.12 × 1016 cm−3 and 1.01 cm2/(V·s, respectively. Crystals of SbTeI are characterized by XRD, SEM, and Raman analysis. Electrical activation energy is found to be 0.52 eV. It is suggested that this material may be studied for its application as a superconductor with Tc higher than room temperature.

X-ray photoelectron spectra and electronic structure of quasi-one-dimensional SbSeI crystals

Directory of Open Access Journals (Sweden)

J.Grigas

2007-01-01

Full Text Available The paper presents the X-ray photoelectron spectra (XPS of the valence band (VB and of the principal core levels from the (110 and (001 crystal surfaces for the quasi-one-dimensional high permittivity SbSeI single crystal isostructural to ferroelectric SbSI. The XPS were measured with monochromatized Al Ka radiation in the energy range of 0-1400 eV at room temperature. The VB is located from 1.6 to 20 eV below the Fermi level. Experimental energies of the VB and core levels are compared with the results of theoretical ab initio calculations of the molecular model of the SbSeI crystal. The electronic structure of the VB is revealed. Shifts in the core-level binding energies of surface atoms relative to bulk ones, which show a dependency on surface crystallography, have been observed. The chemical shifts of the core levels (CL in the SbSeI crystal for the Sb, I and Se states are obtained.

Phase diagram of the Sb-Se-I system and thermodynamic properties of SbSeI

International Nuclear Information System (INIS)

Aliev, Z.S.; Musaeva, S.S.; Babanly, D.M.; Shevelkov, A.V.; Babanly, M.B.

2010-01-01

The Sb-Se-I system was investigated by using the DTA and XRD analyses and EMF measurements with an antimony electrode. The T-x diagram of the binary Sb-I system was accurately redefined. A number of polythermal sections and the projection of the liquidus surface were constructed. The fields of the primary crystallization, as well as the types and coordinates of non- and monovariant equilibria were determined. It is shown that the quasi-binary sections Sb 2 Se 3 -SbI 3 , Sb-SbSeI, SbI 3 -Se, and SbSeI-Se triangulate the Sb-Se-I system, leading to five independent subsystems. A broad area of immiscibility, that overlaps a certain part of the antimony primary crystallization field, was found. From the EMF measurements, the partial molar functions of antimony (ΔG-bar, ΔH-bar, ΔS-bar) as well as standard integral thermodynamic functions of SbSeI were calculated. The latter were found to have the following values: ΔG f,298 0 =-80.12±1.81kJ/mol; ΔH f,298 0 =-77.3±1.8kJ/mol; S 298 0 =155.2±9.5J/(molK).

Phase diagram of the Sb-Se-I system and thermodynamic properties of SbSeI

Energy Technology Data Exchange (ETDEWEB)

Aliev, Z S; Musaeva, S S; Babanly, D M [Baku State University, General and Inorganic Chemistry Department (Azerbaijan); Shevelkov, A.V., E-mail: shev@inorg.chem.msu.r [Moscow Lomonosov State University, Chemistry Department (Russian Federation); Babanly, M.B., E-mail: Babanly_mb@rambler.r [Baku State University, General and Inorganic Chemistry Department (Azerbaijan)

2010-09-03

The Sb-Se-I system was investigated by using the DTA and XRD analyses and EMF measurements with an antimony electrode. The T-x diagram of the binary Sb-I system was accurately redefined. A number of polythermal sections and the projection of the liquidus surface were constructed. The fields of the primary crystallization, as well as the types and coordinates of non- and monovariant equilibria were determined. It is shown that the quasi-binary sections Sb{sub 2}Se{sub 3}-SbI{sub 3}, Sb-SbSeI, SbI{sub 3}-Se, and SbSeI-Se triangulate the Sb-Se-I system, leading to five independent subsystems. A broad area of immiscibility, that overlaps a certain part of the antimony primary crystallization field, was found. From the EMF measurements, the partial molar functions of antimony ({Delta}G-bar, {Delta}H-bar, {Delta}S-bar) as well as standard integral thermodynamic functions of SbSeI were calculated. The latter were found to have the following values: {Delta}G{sub f,298}{sup 0}=-80.12{+-}1.81kJ/mol; {Delta}H{sub f,298}{sup 0}=-77.3{+-}1.8kJ/mol; S{sub 298}{sup 0}=155.2{+-}9.5J/(molK).

SBSI: an extensible distributed software infrastructure for parameter estimation in systems biology.

Science.gov (United States)

Adams, Richard; Clark, Allan; Yamaguchi, Azusa; Hanlon, Neil; Tsorman, Nikos; Ali, Shakir; Lebedeva, Galina; Goltsov, Alexey; Sorokin, Anatoly; Akman, Ozgur E; Troein, Carl; Millar, Andrew J; Goryanin, Igor; Gilmore, Stephen

2013-03-01

Complex computational experiments in Systems Biology, such as fitting model parameters to experimental data, can be challenging to perform. Not only do they frequently require a high level of computational power, but the software needed to run the experiment needs to be usable by scientists with varying levels of computational expertise, and modellers need to be able to obtain up-to-date experimental data resources easily. We have developed a software suite, the Systems Biology Software Infrastructure (SBSI), to facilitate the parameter-fitting process. SBSI is a modular software suite composed of three major components: SBSINumerics, a high-performance library containing parallelized algorithms for performing parameter fitting; SBSIDispatcher, a middleware application to track experiments and submit jobs to back-end servers; and SBSIVisual, an extensible client application used to configure optimization experiments and view results. Furthermore, we have created a plugin infrastructure to enable project-specific modules to be easily installed. Plugin developers can take advantage of the existing user-interface and application framework to customize SBSI for their own uses, facilitated by SBSI's use of standard data formats. All SBSI binaries and source-code are freely available from http://sourceforge.net/projects/sbsi under an Apache 2 open-source license. The server-side SBSINumerics runs on any Unix-based operating system; both SBSIVisual and SBSIDispatcher are written in Java and are platform independent, allowing use on Windows, Linux and Mac OS X. The SBSI project website at http://www.sbsi.ed.ac.uk provides documentation and tutorials.

Photoconductivity in the chalcohalide semiconductor, SbSeI: a new candidate for hard radiation detection.

Science.gov (United States)

Wibowo, Arief C; Malliakas, Christos D; Liu, Zhifu; Peters, John A; Sebastian, Maria; Chung, Duck Young; Wessels, Bruce W; Kanatzidis, Mercouri G

2013-06-17

We investigated an antimony chalcohalide compound, SbSeI, as a potential semiconductor material for X-ray and γ-ray detection. SbSeI has a wide band gap of 1.70 eV with a density of 5.80 g/cm(3), and it crystallizes in the orthorhombic Pnma space group with a one-dimensional chain structure comprised of infinite zigzag chains of dimers [Sb2Se4I8]n running along the crystallographic b axis. In this study, we investigate conditions for vertical Bridgman crystal growth using combinations of the peak temperature and temperature gradients as well as translation rate set in a three-zone furnace. SbSeI samples grown at 495 °C peak temperature and 19 °C/cm temperature gradient with 2.5 mm/h translation rate produced a single phase of columnar needlelike crystals aligned along the translational direction of the growth. The ingot sample exhibited an n-type semiconductor with resistivity of ∼10(8) Ω·cm. Photoconductivity measurements on these specimens allowed us to determine mobility-lifetime (μτ) products for electron and hole carriers that were found to be of similar order of magnitude (∼10(-4) cm(2)/V). Further, the SbSeI ingot with well-aligned, one-dimensional columnar needlelike crystals shows an appreciable response of Ag Kα X-ray.

Investigation of the vibration spectrum of SbSI crystals in harmonic and in anharmonic approximations

International Nuclear Information System (INIS)

Audzijonis, A.; Zigas, L.; Vinokurova, I.V.; Farberovic, O.V.; Zaltauskas, R.; Cijauskas, E.; Pauliukas, A.; Kvedaravicius, A.

2006-01-01

The force constants of SbSI crystal have been calculated by the pseudo-potential method. The frequencies and normal coordinates of SbSI vibration modes along the c (z) direction have been determined in harmonic approximation. The potential energies of SbSI normal modes dependence on normal coordinates along the c (z) direction V(z) have been determined in anharmonic approximation, taking into account the interaction between the phonons. It has been found, that in the range of 30-120 cm -1 , the vibrational spectrum is determined by a V(z) double-well normal mode, but in the range of 120-350 cm -1 , it is determined by a V(z) single-well normal mode

Variation of the energy gap of the SbSI crystals at ferroelectric phase transition

International Nuclear Information System (INIS)

Audzijonis, A.; Zaltauskas, R.; Zigas, L.; Vinokurova, I.V.; Farberovich, O.V.; Pauliukas, A.; Kvedaravicius, A.

2006-01-01

Variation of the forbidden gap of SbSI crystals in the phase transition region is analyzed on the pseudopotential method for antiferroelectric and ferroelectric phase. The band gap at several special points of the Brillouin zone and some characteristic parameters of the band are considered. During the phase transition, the most significant changes are observed with the valence band top at points Q, C, R, H, E and with the conduction band bottom at points H, T and E of the Brillouin zone. At the ferroelectric phase transition, the valence and conduction bands change due to displacement of Sb and S atoms with respect to I and with respect to each other as a result of order-disorder and displacement-type transition. The obtained band gap values agree quite well with the experiment. This is apparently due to application of neutral rather than ionic atomic functions and inclusion of sufficiently many plane waves in the basis set for calculation

Quasi-particle electronic band structure and alignment of the V-VI-VII semiconductors SbSI, SbSBr, and SbSeI for solar cells

Energy Technology Data Exchange (ETDEWEB)

Butler, Keith T. [Centre for Sustainable Chemical Technologies and Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom); McKechnie, Scott; Azarhoosh, Pooya; Schilfgaarde, Mark van [Department of Physics, Kings College London, London WC2R 2LS (United Kingdom); Scanlon, David O. [University College London, Kathleen Lonsdale Materials Chemistry, 20 Gordon Street, London WC1H 0AJ (United Kingdom); Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Walsh, Aron, E-mail: a.walsh@bath.ac.uk [Centre for Sustainable Chemical Technologies and Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom); Global E" 3 Institute and Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of)

2016-03-14

The ternary V-VI-VII chalcohalides consist of one cation and two anions. Trivalent antimony—with a distinctive 5s{sup 2} electronic configuration—can be combined with a chalcogen (e.g., S or Se) and halide (e.g., Br or I) to produce photoactive ferroelectric semiconductors with similarities to the Pb halide perovskites. We report—from relativistic quasi-particle self-consistent GW theory—that these materials have a multi-valley electronic structure with several electron and hole basins close to the band extrema. We predict ionisation potentials of 5.3–5.8 eV from first-principles for the three materials, and assess electrical contacts that will be suitable for achieving photovoltaic action from these unconventional compounds.

The morphologies of fractured surfaces and fracture toughness in some As-Se-Sb-S-I glasses

International Nuclear Information System (INIS)

Lukic, S.R.; Petrovic, D.M.; Skuban, F.; Sidanin, L.; Guth, I.O.

2006-01-01

As part of a general physical characterization of amorphous materials in the pseudobinary system (As 2 Se 3 ) 100-x (SbSI) x type, their indentation fracture toughness was determined. It is a system with the variable ratio of classical amorphous compound As 2 Se 3 and the molecule of antimony sulfoiodide, SbSI, which in the monocrystal form is characterized as ferroelectrics. Because of chalcogenides are generally very brittle and under load they crack very easily, these glasses have been studied with the aim of examining the possibility of obtaining some new structures on the basis of the materials with amorphous internal network, the structures that will have a higher quality in respect of mechanical properties. The morphologies of fractured surfaces were investigated by scanning electron microscope

SED-ED, a workflow editor for computational biology experiments written in SED-ML.

Science.gov (United States)

Adams, Richard R

2012-04-15

The simulation experiment description markup language (SED-ML) is a new community data standard to encode computational biology experiments in a computer-readable XML format. Its widespread adoption will require the development of software support to work with SED-ML files. Here, we describe a software tool, SED-ED, to view, edit, validate and annotate SED-ML documents while shielding end-users from the underlying XML representation. SED-ED supports modellers who wish to create, understand and further develop a simulation description provided in SED-ML format. SED-ED is available as a standalone Java application, as an Eclipse plug-in and as an SBSI (www.sbsi.ed.ac.uk) plug-in, all under an MIT open-source license. Source code is at https://sed-ed-sedmleditor.googlecode.com/svn. The application itself is available from https://sourceforge.net/projects/jlibsedml/files/SED-ED/.

Review on sugar beet salt stress studies in Iran

Science.gov (United States)

Khayamim, S.; Noshad, H.; Jahadakbar, M. R.; Fotuhi, K.

2017-07-01

Increase of saline lands in most regions of the world and Iran, limit of production increase based on land enhancement and also threat of saline water and soils for crop production make related researches and production of salt tolerant variety to be more serious. There have been many researches about salt stress in Sugar Beet Seed Institute of Iran (SBSI) during several years. Accordingly, the new screening methods for stress tolerance to be continued based on these researches. Previous researches in SBSI were reviewed and results concluded to this study which is presented in this article in three categories including: Agronomy, Breeding and Biotechnology. In agronomy researches, suitable planting medium, EC, growth stage and traits for salinity tolerance screening were determined and agronomic technique such as planting date, planting method and suitable nutrition for sugar beet under salt stress were introduced. Sand was salinizied by saline treatments two times more than Perlit so large sized Perlit is suitable medium for saline studies. Sugar beet genotypes screening for salt tolerance and should be conducted at EC=20 in laboratory and EC= 16 dS/M in greenhouse. Although sugar beet seed germination has been known as more susceptible stage to salinity, it seems establishment is more susceptible than germination in which salinity will cause 70-80% decrease in plant establishment. Measurements of leaves Na, K and total carbohydrate at establishment stage would be useful for faster screening of genotypes, based on high and significant correlation of these traits at establishment with yield at harvest time. In breeding section, SBSI genotypes with drought tolerance background would be useful for salinity stress studies and finally there is a need for more research in the field of biotechnology in Iran.

Advanced Unmanned Search System (AUSS) Surface Navigation, Underwater Tracking, and Transponder Network Calibration

Science.gov (United States)

1992-09-01

5 ENTER PULSE REP PERIOD ................................ 900 ENTER RETURN TO TOP LEVEL C-5 26. SBS1 RECEIVER ----- HYDROPHONE ----- HYDRI ...HYDROPHONE ----- HYDRI PRECISION RETURN 1 LEVEL 29. HEADING INPUT ------ GYRO 1 ------ CONTINUE RANGE GATE OFF ----- FILTER OFF RETURN TO TOP LEVEL 30...700 ENTER RETURN TO TOP LEVEL 12. SBSI RECEIVER ------ HYDROPHONE ------ HYDRI PRECISION RETURN 1 LEVEL 13. HEADING INPUT ------ GYRO 1

Processing, microstructure and properties of grain-oriented ferroelectric ceramics

International Nuclear Information System (INIS)

Okazaki, K.; Igarashi, H.; Nagata, K.; Yamamoto, T.; Tashiro, S.

1986-01-01

Grain oriented ferroelectric ceramics such as PbBi/sub 2/Nb/sub 2/O/sub 9/, bismuth compound with layer structure, (PbLa)Nb/sub 2/O/sub 6/, tungsten-bronze structure and SbSI were prepared by an uni-axial hot-pressing, a double-stage hot-pressing and tape casting methods. Microstructures of them were examined by SEM and the prefered textures of the ceramics composed of thin plate and/or needle crystallites were ascertained. Grain orientation effects on electrical, piezoelectric, optical and mechanical properties are discussed

Wavelength modulation spectroscopy of semiconductors

Energy Technology Data Exchange (ETDEWEB)

Kohn, S.E.

1977-10-01

The use of modulation spectroscopy to study the electronic properties of solids has been very productive. The construction of a wide range Wavelength Modulation Spectrometer to study the optical properties of solids is described in detail. Extensions of the working range of the spectrometer into the vacuum ultraviolet are discussed. Measurements of the reflectivity and derivative reflectivity spectra of the lead chalcogenides, the chalcopyrite ZnGeP/sub 2/, the layer compounds GaSe and GaS and their alloys, the ferroelectric SbSI, layer compounds SnS/sub 2/ and SnSe/sub 2/, and HfS/sub 2/ were made. The results of these measurements are presented along with their interpretation in terms of band structure calculations.

The morphologies of fractured surfaces and fracture toughness in some As-Se-Sb-S-I glasses

Energy Technology Data Exchange (ETDEWEB)

Lukic, S.R. [Department of Physics, Faculty of Sciences, University of Novi Sad, Trg D. Obradovica 4, 21000 Novi Sad (Serbia and Montenegro)]. E-mail: svetdrag@im.ns.ac.yu; Petrovic, D.M. [Department of Physics, Faculty of Sciences, University of Novi Sad, Trg D. Obradovica 4, 21000 Novi Sad (Serbia and Montenegro); Skuban, F. [Department of Physics, Faculty of Sciences, University of Novi Sad, Trg D. Obradovica 4, 21000 Novi Sad (Serbia and Montenegro); Sidanin, L. [Department for Production Engineering, Faculty of Technical Sciences, University of Novi Sad, Trg D. Obradovica 6, 21000 Novi Sad (Serbia and Montenegro); Guth, I.O. [Department of Physics, Faculty of Sciences, University of Novi Sad, Trg D. Obradovica 4, 21000 Novi Sad (Serbia and Montenegro)

2006-09-15

As part of a general physical characterization of amorphous materials in the pseudobinary system (As{sub 2}Se{sub 3}){sub 100-x}(SbSI) {sub x} type, their indentation fracture toughness was determined. It is a system with the variable ratio of classical amorphous compound As{sub 2}Se{sub 3} and the molecule of antimony sulfoiodide, SbSI, which in the monocrystal form is characterized as ferroelectrics. Because of chalcogenides are generally very brittle and under load they crack very easily, these glasses have been studied with the aim of examining the possibility of obtaining some new structures on the basis of the materials with amorphous internal network, the structures that will have a higher quality in respect of mechanical properties. The morphologies of fractured surfaces were investigated by scanning electron microscope.

Analysis of the dimerized Sb/Si(001)-(2x1) surface by x-ray standing waves

International Nuclear Information System (INIS)

Lyman, P.F.; Qian, Y.; Bedzyk, M.J.

1994-12-01

X-ray standing wave measurements were undertaken to study the bonding position of Sb adatoms on the Sb-saturated Si(001)-(2x1) surface. Using the (004) and (022) Bragg reflections, the authors find that the Sb atoms form dimers, and that the center of the Sb ad-dimers lies 1.64 angstrom above the bulk-like Si(004) surface atomic plane. These in-plane results are compared to two structural models consisting of dimers whose bonds are parallel to the surface plane and whose centers are either shifted or unshifted (parallel to the dimer bond direction) relative to the underlying substrate planes. The authors thus find two special cases consistent with these data: one with symmetric (unshifted) dimers having a dimer bond length of 2.81 angstrom, and the other with midpoint-shifted dimers, having a bond length of 2.88 angstrom and a lateral shift of 0.21 angstrom

Electronic structure of the BiSI cluster

Energy Technology Data Exchange (ETDEWEB)

Audzijonis, A. [Department of Physics, Vilnius Pedagogical University, Studentu 39, LT-08106 Vilnius (Lithuania); Gaigalas, G. [Department of Physics, Vilnius Pedagogical University, Studentu 39, LT-08106 Vilnius (Lithuania); Institute of Theoretical Physics and Astronomy, Vilnius University, A. Gostauto 12, LT-01108 Vilnius (Lithuania); Zigas, L. [Department of Physics, Vilnius Pedagogical University, Studentu 39, LT-08106 Vilnius (Lithuania)]. E-mail: kkol@vpu.lt; Pauliukas, A. [Department of Physics, Vilnius Pedagogical University, Studentu 39, LT-08106 Vilnius (Lithuania); Zaltauskas, R. [Department of Physics, Vilnius Pedagogical University, Studentu 39, LT-08106 Vilnius (Lithuania); Cerskus, A. [Department of Physics, Vilnius Pedagogical University, Studentu 39, LT-08106 Vilnius (Lithuania); Narusis, J. [Department of Physics, Vilnius Pedagogical University, Studentu 39, LT-08106 Vilnius (Lithuania); Institute of Theoretical Physics and Astronomy, Vilnius University, A. Gostauto 12, LT-01108 Vilnius (Lithuania); Kvedaravicius, A. [Department of Physics, Vilnius Pedagogical University, Studentu 39, LT-08106 Vilnius (Lithuania)

2007-03-15

The energy levels of valence bands (VB) and core levels (CL) of the BiSI crystals have been investigated theoretically. The molecular model of this crystal was used for calculation of VB and CL by the unrestricted Hartree-Fock method using GAMESS program, with Hw and MINI basis set. The molecular cluster consisting of 20 molecules of BiSI was used for calculations of averaged total density of states including atom vibrations. The spectra of averaged total density of states from VB of BiSI cluster has been compared with experimental X-ray photoelectron spectra (XPS) of VB of SbSI crystal. The results clarify that the atomic vibrations is one of possible reasons for the smoother appearance of the experimental XPS. The investigation of vibrational spectrum reveals new experimental information about the reflection spectrum of BiSI crystals. The cluster model calculations have shown that the splitting of the CL in the BiSI may be caused by the photoelectron emission from the atoms at the surface that is in different valence states. The cluster model calculation showed that splitting energy of CL depends on difference of ionic charges of the same atoms at the edges of BiSI cluster.

Electronic structure of the BiSI cluster

International Nuclear Information System (INIS)

Audzijonis, A.; Gaigalas, G.; Zigas, L.; Pauliukas, A.; Zaltauskas, R.; Cerskus, A.; Narusis, J.; Kvedaravicius, A.

2007-01-01

The energy levels of valence bands (VB) and core levels (CL) of the BiSI crystals have been investigated theoretically. The molecular model of this crystal was used for calculation of VB and CL by the unrestricted Hartree-Fock method using GAMESS program, with Hw and MINI basis set. The molecular cluster consisting of 20 molecules of BiSI was used for calculations of averaged total density of states including atom vibrations. The spectra of averaged total density of states from VB of BiSI cluster has been compared with experimental X-ray photoelectron spectra (XPS) of VB of SbSI crystal. The results clarify that the atomic vibrations is one of possible reasons for the smoother appearance of the experimental XPS. The investigation of vibrational spectrum reveals new experimental information about the reflection spectrum of BiSI crystals. The cluster model calculations have shown that the splitting of the CL in the BiSI may be caused by the photoelectron emission from the atoms at the surface that is in different valence states. The cluster model calculation showed that splitting energy of CL depends on difference of ionic charges of the same atoms at the edges of BiSI cluster

Sexual knowledge, attitude, behaviors and sources of influences in Urban college youth: A study from India

Directory of Open Access Journals (Sweden)

Siddharth Dutt

2017-01-01

Full Text Available Background: The study was undertaken as there is very less literature related to sources of influence for sexual knowledge and attitude toward sex and sexual behaviors of youth in India. Aim: The objectives of the study were to explore sexual knowledge, attitudes, behaviors and the sources of influence and also to examine the relationship between sexual knowledge, attitude and behaviors in the youth. Method: The sample was selected from colleges using purposive sampling method and from the community using snowball method (n = 300. The tools used were sociodemographic data sheet, Sexual Knowledge and Attitude Questionnaire (SKAQ-II and Sexual Behavior and Sources of Influence (SBSI scale. Results: Descriptive statistics and correlation was done to analyze the data. The youth had poor sexual knowledge; there was positive relationship between sexual knowledge and attitudes. Sexual behaviors through media and with self or others were found to be low. Internet was found to be the major source for gathering information and was considered the most reliable source. Conclusion: Indian college youth continue to have poor sexual knowledge. Internet is a major source of information and is considered as the most reliable one among youth. More knowledge about sex is associated with liberal attitude toward sex.