Extended Data Fig. 4: Ranges of driving forces for various systems, where superoxide oxidation occurs.

a, Comparison of individual kinetic parabolas as determined for mediated superoxide oxidation. Curves for MeCN are the Marcus fits in Fig. 2. For TEGDME the ³O₂ parabola is the Marcus fit to data in Extended Data Fig. 1. The parabola for ¹O₂ evolution could not be measured in TEGDME, and is hence constructed using \({\triangle G}_{1\leftarrow 3}^{\circ }\) = 0.84 eV and Z_el,1 = 6.3 × Z_el,3 as determined with MeCN (Fig. 2). b, Ranges of driving forces for cation-induced O₂^– disproportionation (DISP) and for the indicated redox couples as defined in c and d. c, Commonly suggested peroxocarbonate species that form from O₂^– in contact with CO₂ (refs. ^41,42,43,44). For example, the superoxo species \({{\rm{CO}}}_{4}^{{\rm{\bullet }}-}\) or \({{\rm{C}}}_{2}{{\rm{O}}}_{6}^{{\rm{\bullet }}-}\) were suggested to be reduced by \({{\rm{O}}}_{2}^{-}\), liberating O₂. Kang’s group⁴ suggested using DFT further peroxocarbonate redox couples and their redox potentials relative to \({{\rm{O}}}_{2}^{-}\)/³O₂ (shown in b). d, Reactions of acyl and alkyl peroxides in contact with \({{\rm{O}}}_{2}^{-}\) which were found to form or not to form ¹O₂ (refs. ^45,46) as explicable by their reduction potentials (shown in b).