%0 Journal Article
%T Water solubility in calcium aluminosilicate glasses investigated by first principles techniques
%+ Laboratoire des colloïdes, verres et nanomatériaux (LCVN)
%A Bouyer, F.
%A Geneste, G.
%A Ispas, Simona
%A Kob, Walter
%A Ganster, Patrick
%< avec comité de lecture
%Z LCVN:10-131
%@ 0022-4596
%J Journal of Solid State Chemistry
%I Elsevier
%V 183
%N 12
%P 2786
%8 2010-12-01
%D 2010
%R 10.1016/j.jssc.2010.08.031
%K Glass leaching
%K Reactivity in glass
%K Aluminosilicate
%K Hydrolysis
%K First-principles calculations
%K SIESTA
%Z Physics [physics]/Condensed Matter [cond-mat]/Disordered Systems and Neural Networks [cond-mat.dis-nn]
%Z Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Journal articles
%X First-principles techniques have been employed to study the reactivity of water into a calcium aluminosilicate glass. In addition to the well known hydrolysis reactions Si-O-Si+h2O->Si-OH + Si-OH and Si-O-Al+h2O-> Si-OH+Al-OH, a peculiar mechanism is found, leading to the formation of an AlO3–H2O entity and the breaking of Al–O–Si bond. In the glass bulk,most of the hydrolysis reactions are endothermic. Only a few regular sites are found reactive (i.e. in association with an exothermic reaction), and in that case, the hydrolysis reaction leads to a decrease of the local disorder in the amorphous vitreous network. Afterwards, we suggest that ionic charge compensators transform into network modifiers when hydrolysis occurs, according to a global process firstly suggested by Burnham in 1975. Our theoretical computations provide a more general model of the first hydrolysis steps that could help to understand experimental data and water speciation in glasses.
%G English
%L hal-00547893
%U https://hal.science/hal-00547893
%~ CNRS
%~ UNIV-MONTP2
%~ LCVN
%~ UNIV-MONTPELLIER
%~ UM1-UM2