Potential energy surface Preexponential factor

Strong interactions are observed between the reacting solute and the medium in charge transfer reactions in polar solvents in such a case, the solvent effects cannot be reduced to a simple modification of the adiabatic potential controlling the reactions, since the solvent nuclear motions may become decisive in the vicinity of the saddle point of the free energy surface (FES) controlling the reaction. Also, an explicit treatment of the medium coordinates may be required to evaluate the rate constant preexponential factor. 

The preexponential factor, Aeo, depends on the dielectric properties of the buffer and the zeta potential at the surface of the packing. Beo represents the activation energy associated with the migration process. 

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