THE STRUCTURE AND VIBRATIONAL EXCITATIONS OF SIMPLE GLASSES

This paper gives careful definitions of the four ranges of order in an amorphous solid: short, intermediate, long and global. These ranges are used to catalog all of the elements of order in the Zachariasen-Warren continoous random network model of amorphous SiO2, and are also recommended to catalog the order in any other homogeneous or heterogeneous model for glass structure. The Sen-Thorpe central-forces-only vibrational model is shown to contain most of the Zachariasen-Warren elements of structural order, and is thereby revealed as a particularly promising first approximation. The infrared, Raman and inelastic neutron scattering spectra of vitreous GeO2 are presented and interpreted extensively, using a central forces model that is augmented with non-central forces. © 1990.