Table 1. Selected bond distances and angles for the nickel carboxylate species 1, 2, 3, 4 and 5, and CO₂-bound CODH.

	1 10	2 11	3	4 10	5	CODH8b
d Ni–C (Å)	1.866(2)	1.882(1)	1.911(2)	1.888(2)	1.858(1)	1.805(31)
d M–O (Å)	—	2.352(1) a	—	1.897(2) b	2.204(1) c	2.030(18) c
		2.217(1) a			2.066(1) c
		2.459(1) a
d C–O (Å)	1.269(3)	1.260(1)	1.247(2)	1.240(3)	1.269(2)	1.298(30)
	1.313(3)	1.271(1)	1.248(2)	1.296(3)	1.289(2)	1.316(30)
Δd C–O (Å)	0.044	0.011	0.001	0.056	0.020	0.018
∠O–C–O (°)	119.6(2)	124.0(1)	128.4(2)	123.7(2)	116.5(1)	117.2(26)

^aM = Na.

^bM = Ni.

^cM = Fe.