SI-O BONDING IN NA2O-TIO-SIO2 AND K2O-TIO2 - SIO2 GLASSES AS STUDIED BY SIK-BETA-X-RAY FLUORESCENCE AND INFRARED-ABSORPTION SPECTROSCOPY

The SiK β fluorescence X-ray and infra-red absorption spectra of Na2O-TiO2-SiO2 and K2O-TiO2-SiO2 glasses have been measured in order to study the Si-O bonding as a function of the composition of glass. The chemical shifts of the SiK β peak relative to that of silica glass [Δλ=λ(SiO2)-λ(specimen)>0] and the wavenumbers of the infra-red absorption peaks around 950cm-1 and 1100 cm-1 have been determined from the spectra. The SiK β chemical shift in both series of glasses increased with increasing total content of R2O and TiO2 and with decreasing ratio of TiO2/(K2O+TiO2), where R2O represents Na2O or K2O. The infra-red peaks around 950 cm-1 and 1100 cm-1 shifted towards lower wavenumbers with increasing total content of R2O and TiO2 and with decreasing ratio of TiO2/(R2O+TiO2). These experimental facts were interpreted as showing that the Si-O bond in glass was weakened as the total content of R2O and TiO2 increased and that the Si-O bond was weakened by R2O more than by TiO2. © 1979 Chapman and Hall Ltd.