Thus, these ΔG° values confirm that the PCET mechanism in Figure alone cannot explain the reason for the higher reactivity of RsvH3 and PtsH than the others toward electrogenerated O2 shown in the CVs. These results are independent of the computational method, three density functionals yielding similar energies for the PCET. 1 Proton transfer (PT1-PT4) and electron transfer (ET1-ET3). The values for concerted correspond to sums of those for ET2 and PT4 (ET3 and PT3). The values for total correspond to sums those for one ET and two PTs. 3 PT1 and PT2 occur at 3OH of RsvH3, and PT3 and PT4 at 4'OH.