THE INFLUENCE OF THE STATIC PERMITTIVITY OF A SOLVENT ON THE MAGNITUDE OF MAGNETIC-FIELD EFFECTS IN THE RECOMBINATION OF TRIPLET RADICAL-ION PAIRS IN PHOTOINDUCED ELECTRON-TRANSFER REACTIONS

The dependence of the effect of magnetic field on the dielectric const ant epsilon was studied for the reactions of photoinduced electron tra nsfer in the pyrene-N,N-diethylaniline system. It was shown that the t ime dependence of the magnetic effect changes considerably with varyin g epsilon: for a time longer than 0.5 mu s, the magnitude of the magne tic effect decreases with time after photoexcitation of the system or is almost constant at epsilon < 100 or epsilon > 100, respectively. Co ntinuous measurements show that the magnetic effect increases monotoni cally with an increase in epsilon and reaches a value close to the gre atest possible value at epsilon = 190. The observed changes in the mag netic effect are explained in the framework of a qualitative hypothesi s on the predominate decay of homogeneous radical ion pairs on increas ing the dielectric permittivity of the medium.