Heterogeneous electron transfer intrinsic rate constant

Figure 11. Free energy relationship for the intrinsic rate constant (log kt) for heterogeneous electron transfer.

Secondly, Fig. 5 shows that the polymeric rate constants parallel values of heterogeneous rate constants that have been observed for the electrochemical reactions of solutions of the corresponding dissolved porphyrin monomers. (The slope of the line is 0.5). This re-emphasizes what was said above, that measurements of electron hopping in polymers can give rate constants that are meaningful in the context of the metalloporphyrin s intrinsic electron transfer chemistry. 

Ew, any characteristic potential of the wave E1/2, Ep, Ep/2, E°, standard reduction potential of the electron transfer step, involving an exchange of n electrons (n > 0 for a reduction n < 0 for an oxidation). intrinsic standard heterogeneous rate constant k, rate constant of the homogeneous follow-up chemical reaction. Chemically reversible or irreversible (see footnote page 55). 

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