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Title: Reverse Monte Carlo analysis of the local order in liquid Ge{sub 0.15}Te{sub 0.85} alloys combining neutron scattering and x-ray absorption spectroscopy

Abstract

The structure of liquid Ge{sub 0.15}Te{sub 0.85} alloys that exhibit a density anomaly between 633 K and 733 K at ambient pressure was investigated using x-ray absorption spectroscopy at the Ge K edge. Using a reverse Monte Carlo method to combine the present results with neutron scattering data, we show that the volume contraction is associated with an increase of the first neighbor coordination number around both Ge and Te by about one atom. The coordination number of Ge increases from 3{+-}0.3 to 4.1{+-}0.3. These results support an interpretation of the density anomaly in terms of the same Peierls-like distortion mechanism acting in the liquid state and in the neighboring (pure Te and GeTe compound) phases.

Authors:
; ; ; ;  [1];  [2];  [3];  [4];  [2]
  1. Laboratoire TECSEN, UMR 6122, CNRS-Universite Paul Cezanne, Campus de St Jerome, 13397 Marseille Cedex 20 (France)
  2. (France)
  3. (France) and European Synchroton Radiation Facility, 6 rue Jules Horowitz, Boite Postale 220, 38043 Grenoble (France)
  4. (Belgium)
Publication Date:
OSTI Identifier:
20719784
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 72; Journal Issue: 17; Other Information: DOI: 10.1103/PhysRevB.72.174209; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; ABSORPTION SPECTROSCOPY; COORDINATION NUMBER; DENSITY; GERMANIUM ALLOYS; GERMANIUM TELLURIDES; LIQUIDS; MONTE CARLO METHOD; NEUTRON DIFFRACTION; TELLURIUM ALLOYS; TEMPERATURE DEPENDENCE; X-RAY SPECTRA; X-RAY SPECTROSCOPY

Citation Formats

Coulet, Marie-Vanessa, Testemale, Denis, Hazemann, Jean-Louis, Gaspard, Jean-Pierre, Bichara, Christophe, SNBL/ESRF, 6 rue Jules Horowitz, Boite Postale 220, 38043, Grenoble, Laboratoire de Cristallographie, 25 Avenue des Martyrs, Boite Postale 166, 38043 Grenoble, Physique de la Matiere Condensee, B5, Universite de Liege, B4000 Sart-Tilman, and Centre de Recherches en Matiere Condensee et Nanosciences-CNRS, Campus de Luminy, Case 913, F13288 Marseille. Reverse Monte Carlo analysis of the local order in liquid Ge{sub 0.15}Te{sub 0.85} alloys combining neutron scattering and x-ray absorption spectroscopy. United States: N. p., 2005. Web. doi:10.1103/PhysRevB.72.174209.
Coulet, Marie-Vanessa, Testemale, Denis, Hazemann, Jean-Louis, Gaspard, Jean-Pierre, Bichara, Christophe, SNBL/ESRF, 6 rue Jules Horowitz, Boite Postale 220, 38043, Grenoble, Laboratoire de Cristallographie, 25 Avenue des Martyrs, Boite Postale 166, 38043 Grenoble, Physique de la Matiere Condensee, B5, Universite de Liege, B4000 Sart-Tilman, & Centre de Recherches en Matiere Condensee et Nanosciences-CNRS, Campus de Luminy, Case 913, F13288 Marseille. Reverse Monte Carlo analysis of the local order in liquid Ge{sub 0.15}Te{sub 0.85} alloys combining neutron scattering and x-ray absorption spectroscopy. United States. doi:10.1103/PhysRevB.72.174209.
Coulet, Marie-Vanessa, Testemale, Denis, Hazemann, Jean-Louis, Gaspard, Jean-Pierre, Bichara, Christophe, SNBL/ESRF, 6 rue Jules Horowitz, Boite Postale 220, 38043, Grenoble, Laboratoire de Cristallographie, 25 Avenue des Martyrs, Boite Postale 166, 38043 Grenoble, Physique de la Matiere Condensee, B5, Universite de Liege, B4000 Sart-Tilman, and Centre de Recherches en Matiere Condensee et Nanosciences-CNRS, Campus de Luminy, Case 913, F13288 Marseille. Tue . "Reverse Monte Carlo analysis of the local order in liquid Ge{sub 0.15}Te{sub 0.85} alloys combining neutron scattering and x-ray absorption spectroscopy". United States. doi:10.1103/PhysRevB.72.174209.
@article{osti_20719784,
title = {Reverse Monte Carlo analysis of the local order in liquid Ge{sub 0.15}Te{sub 0.85} alloys combining neutron scattering and x-ray absorption spectroscopy},
author = {Coulet, Marie-Vanessa and Testemale, Denis and Hazemann, Jean-Louis and Gaspard, Jean-Pierre and Bichara, Christophe and SNBL/ESRF, 6 rue Jules Horowitz, Boite Postale 220, 38043, Grenoble and Laboratoire de Cristallographie, 25 Avenue des Martyrs, Boite Postale 166, 38043 Grenoble and Physique de la Matiere Condensee, B5, Universite de Liege, B4000 Sart-Tilman and Centre de Recherches en Matiere Condensee et Nanosciences-CNRS, Campus de Luminy, Case 913, F13288 Marseille},
abstractNote = {The structure of liquid Ge{sub 0.15}Te{sub 0.85} alloys that exhibit a density anomaly between 633 K and 733 K at ambient pressure was investigated using x-ray absorption spectroscopy at the Ge K edge. Using a reverse Monte Carlo method to combine the present results with neutron scattering data, we show that the volume contraction is associated with an increase of the first neighbor coordination number around both Ge and Te by about one atom. The coordination number of Ge increases from 3{+-}0.3 to 4.1{+-}0.3. These results support an interpretation of the density anomaly in terms of the same Peierls-like distortion mechanism acting in the liquid state and in the neighboring (pure Te and GeTe compound) phases.},
doi = {10.1103/PhysRevB.72.174209},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 17,
volume = 72,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}
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