COMPARISON OF INELASTIC LIGHT AND NEUTRON-SCATTERING IN SE1-XGEX GLASSES - STRUCTURE AND LIGHT-VIBRATION COUPLING COEFFICIENT FREQUENCY-DEPENDENCE

We report Raman scattering investigations of the structural evolution of Se1-xGex glasses for 0 less than or equal to x less than or equal t o 0.4. The correlation between the 150-280 cm(-1) spectral range and t he boson peak allows one to determine the different stages of this evo lution. The comparison of the low-frequency Raman scattering measureme nts and the density of vibrational states obtained by inelastic neutro n scattering is used for the light-vibration coupling coefficient dete rmination. This coupling coefficient exhibits a cross-over correspondi ng to frequency of the maximum of the cluster size distribution. Final ly, in the framework of a heterogeneous medium, the analysis of the lo w-frequency inelastic scattering spectra gives a log-normal domain siz e distribution.