Table 1.

Energy barriers and spin densities for the C-H and N-H activations with EEFs oriented orthogonal to the Fe(IV)=O bond reaction axis, calculated at the B1 and B2+ZPE levels of theory.

Electric field strength (au)	Barrier for C-H (kcal/mol)	Barrier for N-H (kcal/mol)	Difference (kcal/mol)	Spin density of Fe of Fe(IV)=O in C-H	Spin density of O of Fe(IV)=O in C-H	Spin density of Fe of Fe(IV)=O in N-H	Spin density of O of Fe(IV)=O in N-H
−0.0025	21.7/20.1	40.3/36.9	18.6/16.8	3.145	0.551	3.149	0.603
0.0000	17.5/16.3	31.8/26.5	14.3/10.2	3.136	0.582	3.145	0.619
0.0025	19.9/17.4	46.1/40.8	26.2/23.4	3.139	0.575	3.153	0.592