Table 2.

Cu–O Bond Lengths in Cu^II– and Cu^III–OH Complexes

complex	XRD CuII–O (Å)a	predicted Badger’s CuIII–O (Å)b	ΔCu(II)–Cu(III) (Å)c	DFT predicted ΔCu(II)–Cu(III) (Å)d
1	1.845(4)	1.80	0.05	0.048
2	1.859(2)	1.81	0.05	0.045
3	1.885(2)e	1.81	0.08f	0.102
	1.891(2)e

^aDetermined from crystal structure, with estimated standard deviations indicated in parentheses.

^bDetermined by Badger’s Rule (Figure 3c) from ν(Cu–O).

^cCu^II–O distance (XRD) minus Cu^III–O distance (predicted by Badger’s rule).

^dCu^II–O distance minus Cu^III–O distance as predicted by DFT, using PBE0/TZVP (ref 3, Table 3).

^eTwo independent molecules in the asymmetric unit.

^fUsing the average Cu^II–O value of the two independent molecules in the asymmetric unit.