Temperature dependance of the density fluctuations of silica by small angle x-ray scattering

R. Le Parc (1) , Bernard Champagnon (1) , Laurent David (2) , A. Faivre (3) , C. Levelut (3) , Ph. Guenot , J.L. Hazemann (4, 5) , C. Rochas (6) , J.-P. Simon (7, 4)

1 LPCML - Laboratoire de Physico-Chimie des Matériaux Luminescents
2 MATEIS - Matériaux, ingénierie et science [Villeurbanne]
3 Laboratoire des Verres
4 ESRF - European Synchrotron Radiation Facility
5 Laboratoire de Cristallographie
6 LSP - Laboratoire de Spectrométrie Physique
7 LTPCM - Laboratoire de thermodynamique et physico-chimie métallurgiques

Low-OH-content silica samples having fictive temperatures in the interval 1000–1500°C, have been studied by small-angle X-ray scattering using synchrotron radiations both at room temperature and from 20 to 1500deg;C. The limit for zero-angle X-ray scattering intensity is analysed in term of density fluctuations. We demonstrate that density fluctuations are strongly related to structural relaxation; both depend on thermal history (i.e. the fictive temperature) of the sample, in the temperature range below Tg.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

R. Le Parc, Bernard Champagnon, Laurent David, A. Faivre, C. Levelut, et al.. Temperature dependance of the density fluctuations of silica by small angle x-ray scattering. Philosophical Magazine B, 2001, 82 (4), pp.431-438. ⟨10.1080/13642810208223131⟩. ⟨hal-00475295⟩