CHARGE-TRANSFER IN SOLID FRACTAL SYSTEMS - LOW CONCENTRATION OF ACCEPTORS

Known charge-transfer kinetics theory for infinite regular space has b een extended to include irregular fractal systems. The probability P(c t)(t) of finding a donor cation state in regular infinite space is lar ger than in fractal space. The back charge transfer effect increases w ith decreasing fractal dimension. The fractal structure of the reactio n space slows down the charge separation. Two theoretical models consi dered are: the method of conditional concentration of molecules and th e model of nearest neighbors. Both models give nearly the same results at low acceptor concentrations. The long-time branch of probabllity P (ct)(t) falls down if back charge transfer takes place. The results ar e good in the limit of low concentrations of acceptors.