One- and two-phonon vibrational spectra of amorphous As- and Sb-chalcogenide systems

One- and two-phonon infrared and Raman spectra of As- and Sb-chalcogenide systems are reported. Both one- and two-phonon Raman and infrared vibrational spectra exhibit two modes type behaviours characteristics to the vibration modes of AsSe₃, AsS₃, and SbSe₃ pyramids. In the infrared spectra, the larger peak shifts are observed for one phonon frequencies than for two phonon frequencies with the change of the composition x, and its suggests rather big local field effects. The two-phonon coupling parameters of the combination modes are estimated.