Effect of pressure on the elastic properties of vitreousAs2S3

Abstract

The elastic properties of amorphous ${\mathrm{As}}_2$ ${\mathrm{S}}_3$ have been measured as a function of hydrostatic pressure up to 20 kbar. The pressure dependence of the isothermal bulk modulus $K_T$ is interpreted in terms of an interatomic potential, consisting of a Lennard-Jones and a Born-Mayer term. It is shown that this potential predicts a structural phase transition at a pressure range 350-400 kbar. A complete correlation is found to exist between the pressure dependence of the elastic properties and the pressure dependence of the rigid-layer modes as measured by Zallen on crystalline ${\mathrm{As}}_2$ ${\mathrm{S}}_3$.