%0 Journal Article
%T Raman scattering study of alpha-quartz and Si(1-x)GexO2 solid solutions
%+ Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM)
%+ Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB)
%+ Laboratoire des colloïdes, verres et nanomatériaux (LCVN)
%A Ranieri, Vincent
%A Bourgogne, David
%A Darracq, Stéphane
%A Cambon, Martine
%A Haines, Julien
%A Cambon, Olivier
%A Le Parc, Rozenn
%A Levelut, Claire
%A Largeteau, Alain
%A Demazeau, Gérard
%< avec comité de lecture
%Z 2009-104 (ICMCB
%@ 1098-0121
%J Physical Review B: Condensed Matter and Materials Physics (1998-2015)
%I American Physical Society
%V 79
%N 22
%P 224304
%8 2009
%D 2009
%R 10.1103/PhysRevB.79.224304
%K germanium
%K librational states
%K quartz
%K Raman spectra
%K solid-state phase transformations
%K thermal stability
%K vibrational modes
%Z PACS: 63.20.-e; 65.40.-b; 61.66.Fn; 61.50.-f
%Z Physics [physics]/Condensed Matter [cond-mat]Journal articles
%X alpha-quartz-type Si1−xGexO2 solid solutions (x=0.06, 0.11, and 0.24) and pure SiO2 were investigated by Raman spectroscopy. Coupled and decoupled vibrational modes were identified at room temperature as a function of composition. Tetrahedral tilting librational modes involved in the displacive alpha<-->beta-quartz phase transition are decoupled. The wave number of the coupled A1 mode located at 464 cm−1 for pure alpha-quartz was found to vary quite linearly with germanium content. Raman spectra were recorded up to 1473 K. Substitution of germanium in the quartz lattice clearly improves the thermal stability of the alpha phase. The alpha<-->beta-quartz phase transition temperature increases from 846±1 K for x=0 to about 1300±50 K for x=0.24. At the same time, the dynamic disorder observed in quartz well below the transition is reduced in the solid solutions.
%G English
%2 https://hal.science/hal-00434422/document
%2 https://hal.science/hal-00434422/file/2009-104.pdf
%L hal-00434422
%U https://hal.science/hal-00434422
%~ CNRS
%~ UNIV-MONTP1
%~ UNIV-MONTP2
%~ ENSC-MONTPELLIER
%~ ICMCB
%~ ICG
%~ LCVN
%~ CHIMIE
%~ UNIV-MONTPELLIER
%~ UM1-UM2