Inelastic Light Scattering in a Onefold-Coordinated Amorphous Semiconductor

Abstract

The first measurements on low-temperature-deposited thin-film $a$-I are reported. In situ Raman spectra indicate that $a$-I is a onefold-coordinated semiconductor in contrast to other amorphous solids studied to date. The spectra surprisingly differ from those of molecular systems, indicating appreciable intermolecular coupling. Considerable structural disorder is indicated by a fivefold increase in intramolecular bandwidth relative to $c$-I. Delocalized bonding rather than weak directional covalent interactions is suggested for intermolecular coupling in $a$-I.