PNNL

Abstract

The incorporation and reactivity of water molecules in the bulk phases of fused silica are investigated using density functional theory. A wide range of activation barriers for the reaction of water with Si-O bonds to form a pair of Si-OH (silanol) groups is found. The activation energy can be greater than that found in the bulk state of quartz and can also be very low with the possibility of having non-activated processes. The latter is indicative of the role of water in the annealing of silica glass structure and the ability of silica to retain water in the form of silanol groups.