. Author manuscript; available in PMC: 2020 Dec 16.

Published in final edited form as: Inorg Chem. 2019 Dec 2;58(24):16487–16499. doi: 10.1021/acs.inorgchem.9b02432

Table 3.

Comparison of Computed and Experimental g Values and Ligand-Field Splittings for Relevant FeCN Adducts^a

model	method	g₁	g₂	g₃	rms dev^c	Δ (cm⁻¹)	V (cm⁻¹)
1^ox-CN	exptl	1.988	2.161	2.204		4731^d	1094^d
	DFT/PBE0/CP-SCF	2.026	2.127	2.145	0.045
	DFT/B3LYP/CP-SCF	2.020	2.110	2.131	0.055
	CASSCF/NEVPT2	1.946	2.183	2.234	0.032	4321	512
2^ox-CN	exptl	1.964	2.161	2.231		4063^d	1292^d
	CASSCF/NEVPT2	1.953	2.191	2.256	0.023	3886	431
α-CDO	exptl^b	1.937	2.235	2.379		2776^d	1171^d
	CASSCF/NEVPT2	1.914	2.258	2.425	0.032	2833	1056
β-CDO	exptl^b	1.951	2.207	2.344		3126^d	1416^d
	CASSCF/NEVPT2	1.930	2.228	2.350	0.017	3366	1013
Hybrid-1	CASSCF/NEVPT2	1.931	2.206	2.389	na^e	3280	1422
Hybrid-2	CASSCF/NEVPT2	1.971	2.283	2.352	na^e	2849	785

The CASSCF/NEVPT2 calculations employed a CAS(11,13) active space and TZVP basis set.

Reference 30.

rms dev = root-mean-square deviation between experimental and computed g values.

The experimental Δ and V values were calculated using Taylor’s equations for low-spin Fe^III complexes in the absence of iron–ligand covalency, assuming a SOC parameter (λ) of 400 cm⁻¹. See ref 68 for more details.

na = not applicable.