The Structure Of Silica Glass And Its Surface

A detailed structural model of a pristine glass surface is suggested. Based on the strained mixed cluster approach, and derived specifically for silica glass, it indicates that a rather small number of highly strained surface grooves are i) responsible for limitations on mechanical strength; ii) active in chemical reactions leading, for example, to static fatigue in glass fibres, and iii) involved with inward diffusion of gases such as hydrogen and helium. The model also indicates ways in which these grooves could be made less trained and their chemical interactions sealed off. Structural models similar to that proposed should hold for all glasses.