Our systems' adherence to Marcus theory is further supported by the fact that no significant rearrangements occur. Deviations from Marcus theory would be expected in case there is a major solvent rearrangement upon a change of oxidation states, for instance due to the formation or breakage of a bond, or a change in coordination number. The radial distribution functions of (i) the phosphorus atoms (P) of the DNA nucleotides belonging to the QM region and (ii) the water oxygen atoms (O wat ), g(r P -Owat ), were compared for the reduced and oxidized state of each of the four systems (native/8oxoG-containing for regions 1 and 2), and are shown in SI Figures S5 (region 1) and S6 (region 2). Analysis of these DNA-water radial distribution functions show that the water reorganization upon change of oxidation state is very small to negligible for all systems studied. The corresponding contributions to the computed ∆A R→O and λ values are thus very small. This is compatible with the finding that the oxidation process of all systems studied follows Marcus theory, and also validates the use of a non-polarizable force field for water in this study.