Where U SHE is the desired potential vs. SHE, and n is the number of oxygen atoms. By applying this scheme to selected interpolated values of ∆G O for a grid of U SHE , we obtain a set of linear slopes. From this ensemble, it is possible to predict the most stable oxygen ratio within any given potential range by finding the lowest curve in that interval. Following this approach, the oxygen ratio vs. voltage dependence is shown in Figure .