Intermediate polaron pairs formed in the process of charge carrier recombination in poly(p-phenylene vinylenes)

摘要

Abstract: The effect of weak magnetic fields on the photoconductivity of poly(p- phenylene vinylene) (PPV) was observed within the temperature range 130 - 350 K. This effect is attributed to the formation of interchain pairs involving a negative polaron and a positive polaron. A polaron pair is formed as a result of interchain electron transfer from a molecular exciton. The lifetime of a pair is estimated to be within the range of 10$+$MIN@8$/ - 10$+$MIN@9$/ s. Thermal dissociation of a polaron pair produces free charge carriers, and recombination of the pair regenerates a singlet or triplet exciton on a single conjugated segment of a chain.!26