Vibrational spectra of oligothiophenes as model of polythiophenes

Abstract

The vibrational spectra of a few oligomers of thiophene in the solid and solution are studied with the help of quantum mechanical calculations and of the theory of the effective conjugation coordinate recently developed. The aim of the work is to extract from the spectra structural probes to be used in the understanding of the spectra, structure, and thermochromic effects in polyalkylthiophene treated in a paper which follows (paper II).