Vibrational spectra and structure of alkali germanate glasses

摘要: Abstract Numerous structural studies have been carried out so far to elucidate the nature of so-called germanate anomaly, but correct model is still unknown. The objective present paper shed further light on structure alkali glasses, namely those containing sodium and cesium oxides. Two series glass samples were prepared, having molar compositions (100−x)GeO2·xM2O (M=Na 0⩽x⩽35, or M=Cs 0⩽x⩽25). Polarized Raman infrared absorption spectra recorded for these as a function content; reflectivity measurements also Kramers–Kronig analysis near-normal incidence compared with polarized glasses. An overall picture has emerged, which compatible presence fraction higher coordinated Ge atoms, either five-fold six-fold.