Characteristics of Glassy PbO–GeO₂ Binary System by X-Ray Diffraction, Infrared Absorption, Dielectric Constant, and Intrinsic Absorption

Abstract

Four characteristics of the glassy PbO–GeO₂ system were examined. X-ray diffraction pattern of the sample of 50 mol % PbO showed the maximum intensity at d-value 2.885 Å which was in accordance with that of the compound PbO·GeO₂ (relative intensity 60 %). Infrared absorption band of the glassy GeO₂ at 11.5 μ, which would be assigned as ν₃ mode of tetrahedral GeO₄ unit, shifted toward longer wavelength side with increasing PbO content and the shift showed a plateau at 47–50 mol % PbO. Dielectric constant also kept nearly constant value at 47–50 mol % PbO. The wavelengths corresponding to the intrinsic absorption coefficients per PbO mole fraction (e. g. 70 cm⁻¹/m.f.) increase linearly with increasing PbO content, having the inflection point at 45 and 55 mol % PbO. The ionic character of the bond GeO₄–Pb is discussed on the basis of the results.