IONICALLY CONDUCTIVE CHALCOGENIDE GLASSES

A satisfactory understanding of ionic transport mechanisms in glasses has not been achieved to date. Recently, models (coupling model, jump diffusion model, and diffusion controlled relaxation model) based on study of the dynamic of the mobile ions have been developed. To date they have been mainly supported by data obtained on poorly conductive glasses. The very recent results obtained on highly conductive glasses in the systems Ag2X-GeX2-(Agl) (X=S, Se) and Li2S-SiS2-(Lil) in a very large frequency domain by mechanical, electrical, NMR spectroscopies, and by QENS are used to illustrate these models. Also, structural effects influencing the dc conductivity in these glasses are presented and interpreted in terms of the weak electrolyte theory and the Stuart-Anderson approach. © 1992 Academic Press, Inc.