Theoretical treatment of the low magnetic field effect on the intensity of delayed fluorescence in conjugated polymers

Summary form only given. We have calculated the time dependence of magnetic field effect on the intensity of the de layed fluorescence in conjugated polymers in terms of a phenomenological quantum mechanical model. We went out from the assumption, that delayed geminate recombination of charge carriers is the origin of the slow part of fluorescence. This is in agreement with the results of earlier experiments. In this model we considered the magnetic interaction between the 2 spins of the electron and the hole, with adjacent nuclear spins and with the applied magnetic field. The problem was solved by using the time dependend perturbation approach. Experiments on the time dependence of the magnetic field effect on the fluo rescence yield in the conjugated polymers poly(P-phenylene vinylene), in its phenylsubstituted derivatives as well as in oligomeric model compounds by means of a single photon counting technique are in progress.