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Title: Structure and vibrational modes of AgI-doped AsSe glasses: Raman scattering and ab initio calculations

Abstract

We report an investigation of the structure and vibrational modes of (AgI){sub x} (AsSe){sub 100-x}, bulk glasses using Raman spectroscopy and first principles calculations. The short- and medium-range structural order of the glasses was elucidated by analyzing the reduced Raman spectra, recorded at off-resonance conditions. Three distinct local environments were revealed for the AsSe glass including stoichiometric-like and As-rich network sub-structures, and cage-like molecules (As{sub 4}Se{sub n}, n=3, 4) decoupled from the network. To facilitate the interpretation of the Raman spectra ab initio calculations are employed to study the geometric and vibrational properties of As{sub 4}Se{sub n} molecular units that are parts of the glass structure. The incorporation of AgI causes appreciable structural changes into the glass structure. AgI is responsible for the population reduction of molecular units and for the degradation of the As-rich network-like sub-structure via the introduction of As-I terminal bonds. Ab initio calculations of mixed chalcohalide pyramids AsSe{sub m}I{sub 3-m} provided useful information augmenting the interpretation of the Raman spectra. -- Graphical abstract: Raman scattering and ab initio calculations are employed to study the structure of AgI-AsSe superionic glasses. The role of mixed chalcohalide pyramidal units as illustrated in the figure is elucidated. Display Omitted Researchmore » highlights: {yields} Doping binary As-Se glasses with AgI cause dramatic changes in glass structure. {yields} Raman scattering and ab initio calculations determine changes in short- and medium-range order. {yields} Three local environments exist in AsSe glass including a network sub-structure and cage-like molecules. {yields} Mixed chalcohalide pyramids AsSe{sub m}I{sub 3-m} dominate the AgI-doped glass structure.« less

Authors:
 [1];  [1];  [2];  [3];  [4];  [1]
  1. Foundation for Research and Technology Hellas, Institute of Chemical Engineering and High Temperature Chemical Processes, P.O. Box 1414, Patras GR-26504 (Greece)
  2. (Greece)
  3. Institute of Electrochemistry and Energy Systems (IEES), Bulgarian Academy of Sciences, Sofia (Bulgaria)
  4. Laboratory of Thin Film Technology, Department of Physics, University of Chemical Technology and Metallurgy, Sofia (Bulgaria)
Publication Date:
OSTI Identifier:
21494198
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 184; Journal Issue: 2; Other Information: DOI: 10.1016/j.jssc.2010.12.020; PII: S0022-4596(10)00566-9; Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ARSENIC SELENIDES; DOPED MATERIALS; GLASS; RAMAN EFFECT; RAMAN SPECTRA; RAMAN SPECTROSCOPY; SILVER IODIDES; STOICHIOMETRY; ARSENIC COMPOUNDS; CHALCOGENIDES; HALIDES; HALOGEN COMPOUNDS; IODIDES; IODINE COMPOUNDS; LASER SPECTROSCOPY; MATERIALS; SELENIDES; SELENIUM COMPOUNDS; SILVER COMPOUNDS; SPECTRA; SPECTROSCOPY; TRANSITION ELEMENT COMPOUNDS

Citation Formats

Kostadinova, O., Chrissanthopoulos, A., Department of Chemistry, University of Patras, Patras GR-26504, Petkova, T., Petkov, P., and Yannopoulos, S.N., E-mail: sny@iceht.forth.g. Structure and vibrational modes of AgI-doped AsSe glasses: Raman scattering and ab initio calculations. United States: N. p., 2011. Web. doi:10.1016/j.jssc.2010.12.020.
Kostadinova, O., Chrissanthopoulos, A., Department of Chemistry, University of Patras, Patras GR-26504, Petkova, T., Petkov, P., & Yannopoulos, S.N., E-mail: sny@iceht.forth.g. Structure and vibrational modes of AgI-doped AsSe glasses: Raman scattering and ab initio calculations. United States. doi:10.1016/j.jssc.2010.12.020.
Kostadinova, O., Chrissanthopoulos, A., Department of Chemistry, University of Patras, Patras GR-26504, Petkova, T., Petkov, P., and Yannopoulos, S.N., E-mail: sny@iceht.forth.g. 2011. "Structure and vibrational modes of AgI-doped AsSe glasses: Raman scattering and ab initio calculations". United States. doi:10.1016/j.jssc.2010.12.020.
@article{osti_21494198,
title = {Structure and vibrational modes of AgI-doped AsSe glasses: Raman scattering and ab initio calculations},
author = {Kostadinova, O. and Chrissanthopoulos, A. and Department of Chemistry, University of Patras, Patras GR-26504 and Petkova, T. and Petkov, P. and Yannopoulos, S.N., E-mail: sny@iceht.forth.g},
abstractNote = {We report an investigation of the structure and vibrational modes of (AgI){sub x} (AsSe){sub 100-x}, bulk glasses using Raman spectroscopy and first principles calculations. The short- and medium-range structural order of the glasses was elucidated by analyzing the reduced Raman spectra, recorded at off-resonance conditions. Three distinct local environments were revealed for the AsSe glass including stoichiometric-like and As-rich network sub-structures, and cage-like molecules (As{sub 4}Se{sub n}, n=3, 4) decoupled from the network. To facilitate the interpretation of the Raman spectra ab initio calculations are employed to study the geometric and vibrational properties of As{sub 4}Se{sub n} molecular units that are parts of the glass structure. The incorporation of AgI causes appreciable structural changes into the glass structure. AgI is responsible for the population reduction of molecular units and for the degradation of the As-rich network-like sub-structure via the introduction of As-I terminal bonds. Ab initio calculations of mixed chalcohalide pyramids AsSe{sub m}I{sub 3-m} provided useful information augmenting the interpretation of the Raman spectra. -- Graphical abstract: Raman scattering and ab initio calculations are employed to study the structure of AgI-AsSe superionic glasses. The role of mixed chalcohalide pyramidal units as illustrated in the figure is elucidated. Display Omitted Research highlights: {yields} Doping binary As-Se glasses with AgI cause dramatic changes in glass structure. {yields} Raman scattering and ab initio calculations determine changes in short- and medium-range order. {yields} Three local environments exist in AsSe glass including a network sub-structure and cage-like molecules. {yields} Mixed chalcohalide pyramids AsSe{sub m}I{sub 3-m} dominate the AgI-doped glass structure.},
doi = {10.1016/j.jssc.2010.12.020},
journal = {Journal of Solid State Chemistry},
number = 2,
volume = 184,
place = {United States},
year = 2011,
month = 2
}
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