Physical Properties And Raman Spectroscopy Of Geas Sulphide Glasses

Ternary GeAsS glasses have been investigated to determine the compositional dependence of selected physical properties. Although the latter show a linear variation with G:AS ratio at a constant S content, many exhibit a non-linear dependence on the S content at a fixed Ge:As ratio. The trend of optical properties tracks the increasing formation of metal-metal bonds as the S concentration of these glasses is reduced below stoichiometry. Molar volume and thermal expansion coefficient display maxima near an average coordination number of 2.6 for which there is no apparent indication in the Raman spectra.