QUASIELASTIC NEUTRON-SCATTERING FROM A LARGE SINGLE-CRYSTAL OF ALPHA-AG2SE

A quasielastic neutron scattering experiment has been performed on a large single crystal of alpha -Ag//2Se. Spectra were taken at 250 degree C, under different orientations of the crystal. The spectral typically contain a narrow and a broad quasielastic component, plus some broad medium-energy-transfer inelastic scattering. The narrow component is consistent with a continuous model in which the silver ions are assumed to diffuse within a system of less than 100 greater than channels. The broad component is essentially ascribed to a localized irregular movement of the silver ions. The broad inelastic contributions to the spectra reflect highly damped periodic motions of the ions. 51 refs.