Photoexcitations and chemical doping of a soluble conjugated thiophene/phenylene block copolymer

The optical properties and the formation of charged species of a newly synthetized soluble thiophene/phenylene block copolymer are studied with Raman scattering, optical and photoinduced absorption spectroscopies. The optical properties of the copolymer are determined by its low-gap segments, strictly resembling the dialdehyde sexithiophene molecule. Charged species, injected by chemical doping and by photoexcitation, are polarons which accommodate within the thiophene blocks of the copolymer.