Vacuum-ultraviolet spectroscopy of dialkyl polysilanes

We present here a complete experimental determination of the optical properties and electronic structure of the polymers poly(di-n-pentylsilane) and poly(di-n-hexylsilane) from 2 to 44 eV. The electronic structure revealed by these measurements is consistent with the assignment of the higher-energy transitions to the carbon-based sidechains and the lower-energy transitions to the silicon backbone. The transitions attributed to the silicon backbone correlate well with predictions by an independent band-structure calculation using the local-density approximation. © 1991 The American Physical Society.