Correlation of silica glass properties with the infrared spectra

Abstract

Infrared (IR) spectroscopy has been used to interpret structural changes in silica glasses. Specifically, a shift of the Si–O stretching band in IR spectra is used to monitor changes in average Si–O–Si bond angle in the glass structure. A similar structural change is induced by the change of fictive temperature, hydrostatic pressure or compressive stress, with the average Si–O–Si bond angle decreasing with the increase of these parameters. It is anticipated that these similar structural changes would produce a similar change in glass properties. In order to confirm this expectation, HF etch rates of silica glasses were measured as a function of fictive temperature and stress. The experimental results on HF etch rates, together with changes in other glass properties in the literature, were compared with the change in glass structure revealed by IR spectroscopy. It was found that the similar structural change is accompanied by the consistent changes in a variety of glass properties. Monitoring the IR spectra of a silica glass sample, therefore, can be used to deduce changes in glass properties.