Table 3.

OLYP-D3-BJ Calculated Geometrical, Energetic, and net Spin Properties of the Optimized DNC Geometries in the Following Sates: A, Peroxo, Hydroperoxo, P_M, P_R, F, F_H, and O_H.

State	Structure a	Geometry (Å)					ΔG c	Q d	Net Spin e
		Fe-N(H384)	Fe-O1	O1-O2 (O1⋯O2)	Cu-O b	Fe⋯Cu			Fea3	O1	O2	CuB	Y237
		A	Fea33+,LS-O2−•⋯-CuB+,Y-OH	2.15	1.82	1.30			2.95	4.55	0.0	1	0.96	−0.30	−0.51	−0.06	0.0
Peroxo	Fea33+,LS-O22−-CuB2+,Y-OH	2.12	1.80	1.37	1.94	3.88	−26.5	1	0.74	−0.02	−0.21	−0.34	0.0
Hydroperoxo	Fea33+,LS-−OOH-CuB2+,Y-O−	2.07	1.78	1.50	2.11	4.31	−13.1	1	0.88	0.13	−0.06	−0.34	−0.39
PM	Fea34+,IS=O2−⋯HO−-CuB2+,Y-O•	2.10	1.65	2.68	1.90	4.28	−29.3	1	1.29	0.75	−0.21	−0.50	−0.90
PR	Fea34+,IS=O2−⋯HO−-CuB2+,Y-O−	2.09	1.65	2.67	1.91	4.42	−25.4	0	1.28	0.77	−0.21	−0.50	0.0
F	Fea34+,IS=O2−⋯H2O-CuB2+,Y-O−	2.10	1.66	2.52	2.26	4.58	−40.2	1	1.37	0.69	−0.01	−0.36	−0.41
FH	Fea34+,IS=O2−⋯CuB2+,Y-O−	2.15	1.68		2.40	3.81	−46.2	1	1.37	0.67		−0.22	−0.59
OH	Fea33+,HS-OH−-CuB2+,Y-O−	2.43	1.98		1.99	3.58	−56.2	1	4.02	0.13		−0.37	−0.25

^a.LS stands for low-spin, IS is for intermediate-spin, and HS is for high-spin. In state A, the LS Fe_a3³⁺ site is AF-coupled to the O₂^−• radical, and in other states given here, the Fe_a3 site AF-couples to the Cu_B site.

^b.In states A, F_H, and O_H, this is the distance between Cu_B and O1 (see Figure 4). In other states, this is the Cu_B-O2 distance.

^c.Calculated relative free energies at pH = 7 (kcal mol⁻¹), including the spin-projection corrections to the broken-symmetry state energies, the zero-point energy differences, and with the reference to a typical cytochrome c redox potential of E⁰ = +0.22 eV (see details in Supporting Information).

^d.The net charge of the model cluster.

^e.The Mulliken net spin populations (number of unpaired electrons) on Fe_a3, O1, O2, and Cu_B, and on the heavy atoms of the Tyr237 (Y) side chain (the sum total).