RAMAN AND INFRARED-SPECTRA OF AMORPHOUS-SEMICONDUCTORS (GES2)(1-X)(BI2S3)(X) SYSTEMS

Polarized Raman spectra and far-infrared spectra of glasses in the (Ge S2)(1-x)(Bi2S3)(x) system (0 less than or equal to x less than or equa l to 0.6) were measured. The Raman spectra due to the component Bi2S3 had characteristic polarization dependences. The optical constants wer e calculated by Kramers-Kronig analysis of the infrared reflection spe ctra, and were also analyzed by classical oscillator models. These exp erimental results suggest that a pyramid-type molecular model applies for BiS3 for concentrations less than 0.1, but it does not apply for c oncentrations greater than 0.2.