Anion and cation absorption spectra of conjugated oligomers and polymer

Abstract

The absorption spectra of chemically oxidized and reduced phenylenevinylene oligomers and the phenyl-substituted polymer are reported. Based upon the variation of transition energy with chain length at constant spectral shape and the agreement between photoinduced and chemically induced absorption, it is proposed that at moderate doping levels the absorption is due to a Franck-Condon allowed transition of radical anions and cations not reflecting polaron binding energies.