Best fits of simulations to the experimental SSVs using the above-mentioned parameters were then obtained by adjusting the rate constant, k2, for the homogeneous electron transfer between Ru(NH3)6 2+ and S2O8 2-, eq. 2. Our simulations only approximated the observed SSV response due to the non-idealities in the experimental curves, as discussed above. Additionally, we found that the set of voltammograms in Figure acquired at different S2O8 2-concentrations (0.60 to 2.4 mM) could not be fit by a unique value of k2 (see Table ). Rather, the best fits over this concentration range required varying k2 from 1.5 × 10 5 to 6.5 × 10 5 M -1 s -1 with increasing S2O8 In a previous report, we showed that the simulations of the cyclic voltammetric (CV) response for the same system, but using a large glassy carbon electrode (radius = 1.49 mm), were in near-perfect agreement with experimental CVs obtained in solutions containing 1.0 mM Ru(NH3)6 3+ , 0.1 M NaSO4, and S2O8 2-(2 to 8 mM). In addition to the electrode material and size, the only difference between the present and prior experiments is the choice of supporting electrolyte, KCl vs. NaSO4, respectively. A single value of k2 = 2.0 × 10 5 M -1 s -1 for the reaction between Ru(NH3)6 2+ and S2O8 2-(eq. 2) was found to yield good fits to the prior CV results, independent of S2O8 2-concentration, in reasonable agreement with values listed in Table .