A theoretical explanation of the recently observed non-Marcus free energy gap dependence of the charge recombination rate in contact ion pairs is presented. The electron transfer event is described as a nonadiabatic depopulation of the initially excited adiabatic state. This model explains the absence of the normal region. Quantitative predictions based on the perturbation theory in the nonadiabatic interaction show good agreement with experimental results. (C) 2000 American Institute of Physics. [S0021-9606(00)51109-X].