EXCIMERS AND EXCIPLEXES OF CONJUGATED POLYMERS

Observations of intermolecular excimers in several pi-conjugated polym ers and exciplexes of these polymers with tris(p-tolyl)amine are repor ted. It is shown that the luminescence of conjugated polymer thin film s originates from excimer emission and that the generally low quantum yield is the result of self-quenching. Thus, in sufficiently dilute so lution, the ''single-chain'' emission has a quantum yield of unity. Ex ciplex luminescence and exciplex-mediated charge photogeneration have much higher quantum yields than the excimer-mediated photophysical pro cesses. These results provide a basis for understanding and controllin g the photophysics of conjugated polymers in terms of supramolecular s tructure and morphology.