Figure 8.

Relative energies (in kcal/mol) for the structures along the minimum energy path (MEP) for the detachment of the DNA base from Fe and the formation of formaldehyde in the quintet state for the H₂O pathway (a) and OH^– pathway (b). The numbers in the parentheses are reaction barriers, which are the energy differences between intermediates and their corresponding TSs. The ^ISFe^III–O_F reactant (Figure 2) is taken as the reference for each pathway. Carbon atoms are colored in gray, hydrogen in white, nitrogen in blue, oxygen in red, iron in purple, and boundary carbon atoms for pseudo-bond in cyan.