Table 2. Selected bond distances, angles, nitrosyl vibration, and relative free energies for 3 depending on spin-state.

	Open-shell singlet	Closed-shell singlet	Triplet	Experimental
Ni–P1/2 (Å)	2.280/2.333	2.253/2.315	2.265/2.311	2.244(1)/2.223(1)
Ni–N1 (Å)	2.025	2.008	1.961	1.999(4)
Ni–N2 (Å)	1.740	1.701	1.894	1.694(4)
N2–O1 (Å)	1.187	1.191	1.222	1.174(6)
P1–Ni1–P2 (°)	136.7	137.4	166.5	142.5(5)
N1–Ni1–N2 (°)	151.9	153.6	177.6	148.5(2)
Ni1–N2–O1 (Å)	142.7	140.8	128.7	145.4(4)
ν NO (cm–1)	1675.8	1662.6	1498.6	1646
ΔG (kcal mol–1)	0.00	1.99	6.79