Table 1. Average bond-length (Å) and bond-valence-sum (BVS; v.u.) values used to support the assigned oxidation states of the copper and manganese ions.

	Avg. bond length	BVS value	Assigned oxidation state
Mn1	2.171	2.01	2+
Cu1	1.896	2.05	2+
Cu2	1.914	2.11	2+
Cu3	1.921	2.08	2+
Cu4	1.892	2.08	2+
Cu5	1.922	2.07	2+
Cu6	1.912	2.12	2+