The vibrational spectra of v-SiO₂ and SiO₂-GeO₂ glasses

The authors have calculated the vibrational densities of states for v-SiO₂ and the binary v-SiO₂-GeO₂ glasses. The results for v-SiO₂ are in agreement with the neutron scattering spectrum and previous theoretical calculation of Bell et al. (1972). The spectra of v-SiO₂-GeO₂ glasses which contain only a small fraction of GeO₂ are found to have the general features of v-SiO₂, except for a new peak characteristic of Ge doping and a split To-like band which agrees with Raman scattering and can be understood simply by the superposition of the local densities of states of SiO₄ and GeO₄ tetrahedral with different weights.