Comparison of binding strengths of bidentate and monodentate succinate/Glu to Fe and V confirms that bidentate succinate and Glu bind more strongly than their monodentate counterparts for both metals, i.e., we observe Mayer bond orders of 0.82 vs 0.63 for binding to Fe, and a larger difference in bond orders of 0.94 vs 0.56 for binding to V (Figure ). However, their binding strength is much weaker than that of the bidentate aKG for both metals, which could in part be a result of the differences in structures (Figure ). For example, the M-O distances of Fe/V to both O atoms of aKG are shorter by ca. 0.20 Å in comparison to average M-O distances for bidentate succinate (Figure ). We observe comparable binding strengths of both carboxylate ligands, i.e., monodentate (bidentate) Glu binds as strongly as monodentate (bidentate) succinate for Fe and V (Figure ). Comparison of ligand binding strengths between oxo and hydroxo intermediates reveals that, relative to oxo isomers, the binding strength of monodentate Glu is reduced in hydroxo isomers for both metals owing to hydrogen bonding interactions between the hydroxo moiety and Glu (Figure and Supporting Information Figure ). Across all the isomers of oxo, hydroxo, and O2-bound intermediates, we find stronger binding of bidentate succinate, bidentate Glu, and bidentate aKG in V intermediates relative to Fe intermediates (Figure ). This difference in binding strength is most significant for the binding of aKG to the metal center. aKG binds more strongly to V than to Fe (Mayer bond order: 1.81 vs 1.36), likely due to the LS ground state for V in comparison to the HS ground state for Fe (Figure ). However, in oxo and hydroxo isomers, the binding strengths of monodentate succinate and monodentate Glu are comparable between Fe and V intermediates (Figure ). From the analysis of ligand binding strengths, we thus conclude that bidentate succinate is only slightly more strongly bound to the metal than monodentate succinate, and this trend is preserved in both Fe and V active sites. This supports the potential isomerization between isomers of M(IV)=O intermediates to enable HAT during the catalytic cycle and it suggests that V mimics should be suitable to capture this factor in isomerization.