Effect of the excitation pulse frequency on the ultrafast photoinduced electron transfer dynamics

The dependence of the ultrafast photoinduced electron transfer dynamics in donor-acceptor complexes on the excitation pulse carrier frequency (spectral effect) has been investigated in the framework of a model involving three electronic state. The spectral effect has been shown to strongly depend on the angle θ between the reaction coordinate directions corresponding to optical and charge transfer transitions. Describing the solvent as a linear homogenous polar medium and accounting for Coulombic interaction of the transferred charge with the medium polarization fluctuations, the angle θ has been found out to be typically in the area 40 deg. -85 deg. Exactly in this area of θ the spectral effect is predicted to be most pronounced