REORGANIZATION ENERGY OF ELECTRON-TRANSFER IN POLAR LIQUIDS - DEPENDENCE ON REACTANT SIZE, TEMPERATURE AND PRESSURE

The solvent reorganization energy of outer sphere electron transfer in polar liquids is derived in a molecular treatment. The reorganization energy is shown to be the sum of two contributions: the reorganizatio n energy of reorientation of liquid permanent dipoles and the energy o f reorganization of the liquid density. Reorientation of the dipoles g ives the main contribution to the solvent reorganization energy, where as reorganization of the density contributes mainly to the activation entropy which is positive in the normal and negative in the inverted r egions of electron transfer. The reorganization energy of the liquid d ensity contains an explicit temperature dependence which causes the no n-Arrhenius temperature dependence of the rate constant. Entropy, enth alpy and volume of activation are found for several solvents.