A donor-acceptor polymer with a peculiar negative-charge-

Voltammetric and spectrophotometric measurements, in connection with other experimental evidences, revealed a normal oxidative behaviour of Poly(3,3??-dipentoxy-3?-dicyanoethenyl-2,2?:5?,2?terthiophene) (PolyCN) films, but a special reductive comportment, which can be summarised in the trapping of the negative charge achieved during the cathodic scan. Another interesting property of PolyCN films is the tendency to form strong intramolecular (or intermolecular) associations, probably also CT complexes. These properties could account for the failure to improve the photovoltaic performance when PolyCN was engaged in a blend formation with a polythiophene donor.Voltammetric and spectrophotometric measurements, in connection with other experimental evidences, revealed a normal oxidative behaviour of Poly(3,3??-dipentoxy-3?-dicyanoethenyl-2,2?:5?,2?terthiophene) (PolyCN) films, but a special reductive comportment, which can be summarised in the trapping of the negative charge achieved during the cathodic scan. Another interesting property of PolyCN films is the tendency to form strong intramolecular (or intermolecular) associations, probably also CT complexes. These properties could account for the failure to improve the photovoltaic performance when PolyCN was engaged in a blend formation with a polythiophene donor.