IR studies of alkali silicate glasses

Infrared spectra of alkali silicate glasses were studied by the KBr method. In addition to the similarity of the absorption peaks of the SiO linkage observed in the early studies of these systems, it was found that with increasing alkali content new absorption peaks apart from those at 1050–1100 cm −1 arise at different concentrations of K 2O, Na 2O or Li 2O in glass. The new absorption peaks which are attrbuted to the variations of the main structure groupings agree with the abrupt changes of partial molar volume of SiO 2 at eutectic compositions. This is the first time that the abrupt changes of physical properties of silicate glasses have been confirmed directly by an experiment. i.e., by comparing the IR spectra of glasses.