Water-related IR absorption spectra for some phosphate and silicate glasses

The water-related IR absorption spectra of some alkaline earth metaphosphate glasses, sodium silicate glasses, and window glass in the 1300-4000 cm(-1) range are investigated. In the 1500-2600 cm(-1) region, four strong bands are found for all glasses studied. These bands, based on a similarity in their locations to those reported earlier for pyrophosphate glasses, are assigned to different stretching vibrations of the hydroxyl group participating in the strong hydrogen bonding of a single kind. Slight variations in band locations depending on glass composition are shown. For silicate glasses, the peak absorptivities for the low-frequency hydroxyl-related bands around 1590, 1740 and 2100 cm(-1) are found to be greater by similar to 15, 15, and 4-5 times, respectively, than maximum absorptivities in the entire 2300-3700 cm(-1) range. This rise in absorption with a decrease in wavenumber below 2300 cm(-1) is considered to be the reason why literature sources available missed three above bands. A conclusion is made that Scholze's scheme of formation of water-related IR spectra of glasses probably needs reconsidering. (C) 2000 Elsevier Science B.V. All rights reserved.