Effect of spin-orbit interaction on recombination luminescence of dye in films of halogen-containing derivative poly-N-epoxypropylcarbazole

Abstract

A photoluminescence kinetics of a cationic polymethine dye in composite polymer films based on halogen-containing derivatives poly-N-epoxypropylcarbazole (PEPC) has been studied. The observed luminescence kinetics is formed by the fluorescence of the dye and recombination luminescence associated with the formation and recombination of electron-hole pairs (EHP). It was shown, that measuring the external magnetic field effect on the kinetics of dye luminescence in a wide time range made it possible to determine the characteristic times of the recombination processes with the involvement of EHP formed from singlet and triplet excited electronic states of the dye molecules and main channels of electron energy transformation in composite films. An enhancement of the spin-orbit interaction in polymers with different heavy atoms leads to an increase in a value of the magnetic effect (g(B)) in the nanosecond time range and to a decrease in g(B) value in the microsecond time range.