SOLVENT REORGANIZATION ENERGY WITH DIELECTRIC GREEN FUNCTIONAL AND ITS APPLICATION TO RETURN ELECTRON TRANSFER IN TETRACYANOETHYLENE-HEXAMETHYLBENZENE SYSTEM

Abstract

Based on classical electrodynamics, the proper integral formula for general cases is adopted to estimate the electrostatic free energy difference between two given states, e.g. equilibrium and non-equilibrium states in the charging process of solute molecule in solution. With adequate consideration of the change of dielectric property in establishing the non-equilibrium state, the electrostatic free energy for this state can be obtained in a form differing from the traditional theories. The general formula of the solvent reorganization energy is derived according to the definition of the free energy difference between the non-equilibrium and equilibrium states due to the same electronic state of the solute molecule. Applying it to the two-sphere model and single-sphere model, we obtain the new expressions of the solvent reorganization energy, which are convenient to be used in practice. In the investigation of the return electron transfer of tetracyanoethylene-hexmethylbenzene system, good results can be obtained by using our expression when they are compared with those from the experiment.