Heterogeneous Electron Transfer Rate Constants for the Second Reduction Process of Some Dinitroaromatics

Standard heterogeneous electron transfer rate constants k0 for the second reduction process of 1,2-, 1,3- and 1,4-dinitrobenzenes were evaluated by the Gileadi method. The temperature dependences of k0 were investigated using Marcus' and other expression for ∆G*. However, it was found that to explain the values of k0 and its variation with temperature, it might be prudent to take into consideration the dielectric constant near the site of the reactant (the anion radical) and the product (the dianion).