Reduction of photoluminescence quantum yield by interchain interactions in conjugated polymer films

We use new photoluminescence data to conclusively establish that photoexcitation of substituted phenylenevinylene polymer films results in a large quantum yield of nearly nonluminescent interchain excitations at ambient temperatures. These data are acquired in the low excitation density regime where excited state interactions are negligible. This result has significant implications for material design and processing to make polymer light-emitting diodes.