Structure and Vibrational Modes of As-S-Se Glasses: Raman Scattering and Ab Initio Calculations

Samples of As18SxSe82-x glasses were prepared by conventional melt-quenching techniques with As, S and Se of 99.99% purity. Raman spectra of samples were obtained by a Fourier transform Raman spectrometer. In addition, all calculations based on Hartree-Fork theory have been used to investigate the Raman-active modes of AsSnSe3-n clusters. It can be found that the calculated data of basic cluster models are in excellent agreement with observed Raman spectra. We give an explanation about the Raman shift of main vibrational modes in AsSnSe3-n clusters.