INTERCHAIN EXCITATIONS IN CONJUGATED POLYMERS

The luminescence quantum yield is dramatically increased upon going fr om films to dilute blends or solutions of a soluble phenylenevinylene polymer. Nevertheless, direct measurements of the decay dynamics of th e emissive excitons show that their lifetimes are not very different. Separation of the polymer chains suppresses interchain exciton formati on, which otherwise competes favorably with the generation of emissive intrachain excitons in films. We discuss the consequences for the des ign of polymeric systems for optoelectronics.