Specific features of the radiative relaxation of excited states of polymethine dyes of different ionicity in films of photoconductive and nonphotoconductive polymers

Abstract

The spectral and luminescent properties of film composites based on photoconductive poly N epoxipropylcarbazole and nonphotoconductive polyvinylbutyral with admixtures of cationic and anionicpolymethine dyes, as well as the effect of an external magnetic field on these properties, are studied. It is found that the magnetic field affects the intensity and kinetics of the delayed fluorescence and recombination lumi nescence of the cationic dye in photoconductive films. This is explained by specific features of photogenera tion of charge pairs, namely, by the participation of the singlet and triplet excited states of dye molecules in this process, as well as by the singlet–triplet conversion in dye molecules and photogenerated charge pairs.