Ref HAL: hal-01101026_v1
DOI: 10.1021/jp5094383
WoS: 000349059700054
Exporter : BibTex | endNote
29 Citations
Résumé:

When vitreous silica is submitted to high pressures under helium atmosphere, the change in volume observed is much smaller than expected from its elastic properties. 1 It results from helium penetration into the interstitial free volume of the glass network. We present here the results of concurrent spectroscopic experiments using either helium or neon and molecular simulations relating the amount of gas adsorbed to the strain of the network. We show that a generalized poromechanical approach, describing the elastic properties of microporous materials upon adsorption, can be applied success-fully to silica glass in which the free volume exists only at the sub-nanometer scale. In that picture, the adsorption-induced deformation accounts for the small apparent compressibility of silica observed in experiments.