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Title: Structure and dynamics of l-Ge: Neutron scattering experiments and ab initio molecular dynamics simulations

Abstract

We report the first measurements of the dynamics of liquid germanium (l-Ge) by quasielastic neutron scattering on time-of-flight and triple-axis spectrometers. These results are compared with simulation data of the structure and dynamics of l-Ge which have been obtained with ab initio density functional theory methods. The simulations accurately reproduce previous results from elastic and inelastic scattering experiments, as well as the q dependence of the width of the quasielastic signal of the new experimental data. In order to understand some special features of the structure of the liquid we have also simulated amorphous Ge. Overall we find that the atomistic model represents accurately the average structure of real l-Ge as well as the time dependent structural fluctuations. The quasielastic neutron scattering data allows us to investigate to what extent simple theoretical models can be used to describe diffusion in l-Ge.

Authors:
; ; ; ; ;  [1];  [2];  [3];  [4];  [2]
  1. Laboratoire des Colloiedes, Verres et Nanomateriaux, CNRS, UMR 5587, Universite Montpellier 2, 34095 Montpellier Cedex 5, France and Institut Laue-Langevin, BP 156, 38042 Grenoble cedex 9 (France)
  2. (France)
  3. (Switzerland)
  4. (CEA-CNRS), CEA Saclay, 91191 Gif-sur-Yvette cedex (France)
Publication Date:
OSTI Identifier:
20957764
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 10; Other Information: DOI: 10.1103/PhysRevB.75.104208; (c) 2007 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; DENSITY FUNCTIONAL METHOD; DIFFUSION; GERMANIUM; INELASTIC SCATTERING; LIQUIDS; MOLECULAR DYNAMICS METHOD; NEUTRON DIFFRACTION; NEUTRON REACTIONS; QUASI-ELASTIC SCATTERING; SEMICONDUCTOR MATERIALS; SIMULATION; SPECTRA; TIME DEPENDENCE; TIME-OF-FLIGHT METHOD

Citation Formats

Hugouvieux, Virginie, Farhi, Emmanuel, Johnson, Mark R., Juranyi, Fanni, Bourges, Philippe, Kob, Walter, Institut Laue-Langevin, BP 156, 38042 Grenoble cedex 9, Laboratory for Neutron Scattering, ETHZ and PSI, 5232 Villigen, Laboratoire Leon Brillouin, and Laboratoire des Colloiedes, Verres et Nanomateriaux, CNRS, UMR 5587, Universite Montpellier 2, 34095 Montpellier Cedex 5. Structure and dynamics of l-Ge: Neutron scattering experiments and ab initio molecular dynamics simulations. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.104208.
Hugouvieux, Virginie, Farhi, Emmanuel, Johnson, Mark R., Juranyi, Fanni, Bourges, Philippe, Kob, Walter, Institut Laue-Langevin, BP 156, 38042 Grenoble cedex 9, Laboratory for Neutron Scattering, ETHZ and PSI, 5232 Villigen, Laboratoire Leon Brillouin, & Laboratoire des Colloiedes, Verres et Nanomateriaux, CNRS, UMR 5587, Universite Montpellier 2, 34095 Montpellier Cedex 5. Structure and dynamics of l-Ge: Neutron scattering experiments and ab initio molecular dynamics simulations. United States. doi:10.1103/PHYSREVB.75.104208.
Hugouvieux, Virginie, Farhi, Emmanuel, Johnson, Mark R., Juranyi, Fanni, Bourges, Philippe, Kob, Walter, Institut Laue-Langevin, BP 156, 38042 Grenoble cedex 9, Laboratory for Neutron Scattering, ETHZ and PSI, 5232 Villigen, Laboratoire Leon Brillouin, and Laboratoire des Colloiedes, Verres et Nanomateriaux, CNRS, UMR 5587, Universite Montpellier 2, 34095 Montpellier Cedex 5. Thu . "Structure and dynamics of l-Ge: Neutron scattering experiments and ab initio molecular dynamics simulations". United States. doi:10.1103/PHYSREVB.75.104208.
@article{osti_20957764,
title = {Structure and dynamics of l-Ge: Neutron scattering experiments and ab initio molecular dynamics simulations},
author = {Hugouvieux, Virginie and Farhi, Emmanuel and Johnson, Mark R. and Juranyi, Fanni and Bourges, Philippe and Kob, Walter and Institut Laue-Langevin, BP 156, 38042 Grenoble cedex 9 and Laboratory for Neutron Scattering, ETHZ and PSI, 5232 Villigen and Laboratoire Leon Brillouin and Laboratoire des Colloiedes, Verres et Nanomateriaux, CNRS, UMR 5587, Universite Montpellier 2, 34095 Montpellier Cedex 5},
abstractNote = {We report the first measurements of the dynamics of liquid germanium (l-Ge) by quasielastic neutron scattering on time-of-flight and triple-axis spectrometers. These results are compared with simulation data of the structure and dynamics of l-Ge which have been obtained with ab initio density functional theory methods. The simulations accurately reproduce previous results from elastic and inelastic scattering experiments, as well as the q dependence of the width of the quasielastic signal of the new experimental data. In order to understand some special features of the structure of the liquid we have also simulated amorphous Ge. Overall we find that the atomistic model represents accurately the average structure of real l-Ge as well as the time dependent structural fluctuations. The quasielastic neutron scattering data allows us to investigate to what extent simple theoretical models can be used to describe diffusion in l-Ge.},
doi = {10.1103/PHYSREVB.75.104208},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 10,
volume = 75,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
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