DYNAMICS OF LONG-LIVED POLARONS IN POLY(PARA-PHENYLENE)-TYPE LADDER POLYMERS

The X-band spin-1/2 photoluminescence-detected magnetic resonance of p oly(para-phenylene)-type ladder polymer films and solutions are descri bed. The photoluminescence-enhancing resonances are assigned to enhanc ed nonradiative recombination of long-lived polaron pairs, which are s inglet exciton quenching centers. Their behavior is consistent with tw o distinct polaron lifetimes or a very broad distribution of lifetimes ; in solutions they are approximate to 10 longer than in films. Distin ct lifetimes are discussed in relation to longer-lived intrachain inte rconjugation segment and shorter-lived interchain pairs.