CALCULATION OF THE ELECTRONIC FACTOR

Abstract An effective electronic factor Δ for electron transfer (ET) reactions can be calculated as an energy splitting at an avoided crossing. We employed quantum chemical ab initio techniques including correlation and large basis sets. In particular we allowed symmetry relaxation, which gives an important correlation to Koopmans' theorem in cases of a large electron or hole polarization. We obtained encouraging agreement with experimental ET data as well as photoelectron and electron transmission data. The dependence of Δ on the distance betwwen donor and acceptor is exponential if the orbital energy of the transferring electron is well above the orbital energies of the bridge electrons. Semi-empirical spectroscopic methods give qualitatively but not quantitatively correct results.