Chemical and Electrochemical Electron-Transfer Theory

One of the active areas in reaction kinetics during the post-war years has
\nbeen that of electron-transfer reactions. These reactions constitute one type
\nof oxidation-reduction process and include both chemical and electrochemical
\nsystems. Many rate constants have now been measured (1-8) and
\nthey have stimulated a variety of theoretical studies (9-37). The field has
\nbeen characterized by a strong interplay of theory and experiment, which
\nnow includes the testing of theoretically predicted quantitative correlations
\n(34). Because of a certain unique feature of the purely electron-transfer
\nreactions--the absence of bond rupture in the reaction step--these correlations
\nare unusual. They do not have the arbitrary parameters that occur
\nin theoretical studies of most other reactions in chemical kinetics. This review
\nwill be limited to purely electron transfer reactions.