ABSTRACT
The processes involving rearrangement of heavy species have a number of specific features compared with the reactions of purely electron or proton transfer. Since mutual positions of the particles having comparable masses are changed in the course of the reaction, mixing of the normal coordinates occurs as a rule. The activation energy was calculated with the use of a one-dimensional potential energy surface constructed in an empirical way. Quadratic formulae similar to corresponding expressions for electron transfer have sometimes been used for the analysis of the activation free energies of these reactions. The simplest model enabling to take into account the quantum effects in the motion of heavy particles and the mixing of normal coordinates is the model of harmonic vibrations. Another approximation is the adiabatic separation of the proton motion from the motion of heavier atoms.
