Marcus Theory for Outer-Sphere Heterogeneous Electron Transfer:  Predicting Electron-Transfer Rates for Quinones

Steady-state voltammetry is used to measure the heterogeneous electron-transfer rates for the reduction of quinones to determine the dependence of k(0) on molecular size, according to Marcus theory. This dependence is then used to predict the electron-transfer rate constants of related quinones, and the predictions are compared to experimental measurements.