Origin of Rayleigh scattering and anomaly of elastic properties in vitreous and molten GeO2

摘要: Abstract Vitreous (v) and molten (m) GeO 2 were studied by Rayleigh Mandel’shtam–Brillouin scattering spectroscopy high-temperature acoustics. Original measurement apparatus procedure used that included Bayseian deconvolution of light spectra vGeO a specially designed (up to 1500 °C) acoustic interferometer measure temperature frequency dependence ultrasonic (US) velocity attenuation in mGeO . Landau–Placzek ratios for found optically (from the spectrum) acoustically (through Schroeder’s formalism). Dispersion optical other physical parameters many authors is explained existence small amount samples. It means properties are under influence redox synthesis conditions controlling  ↔ GeO coordination [GeO 4 ] ↔ [GeO 6 ] equilibrium Measurements dependencies longitudinal velocities PbO–GeO glass melts as function PbO concentration shows ‘water-like anomaly’ liquid germanates with rich content where sound increases temperature.