Theoretical Studies on Photoinduced Intramolecular Electron Transfer Reorganization Energy of a Series of Organic Donor-acceptor Systems

Photoinduced intramolecular electron transfer reorganization energies involved in a series of electron donor-acceptor systems have been investigated by theoretical calculations according to quantum mechanics treatments of electron transfer.The systems consist of 9,10-dimethoxyanthrecene as electron donor and benzyl group substituted with different electron with drawing groups as electron acceptors linked by Biphenol A.The inner-sphere reoeganization energies were caculated by H_f-change method together with the bond-length change method based on the gemetry of the electron donors and electron acceptors before and after electron transfer optimized by AM1 semiempirical quantum chemical method.The outer-sphere reorganization energies were caculated using the radii of the donors and acceptor and the center-to-centor distance between them based on the geometries of the donors and acceptors optimized by the AM1 quantum mechanics method and the geometries of the donor-acceptor systems optimized by the NMX molecular mechanics method respectively.The total reorganization energy calculations are in good agreement with experiment vlues indicating that all the methods used are feasible.