Copper to Oxygen Bond Distances—Ionic Radii

2 Copper to Oxygen Bond Distances— Ionic Radii 

The copper to oxygen distance will vary according to the oxidation state of copper, the degree of covalency in the bond, and the geometry about the copper atom. The data given below are the averages of reported (and theoretical ionic ) radii obtained from 

This latter distortion is associated with the strong Jahn-Teller effect of the Cu2+ ion. The Jahn-Teller distortion can result in the formation of an elongated octahedron (4 short + 2 long) a square pyramid (4 short + 1 long) or quite commonly a square plane (4 short). 

The tetrahedral Cu04 group is rarely observed and no strong evidence has ever been presented for this highly symmetrical environment about the divalent copper ion. Coordinations higher than VI (or IV + II) are also very rare. Statistical data for Cu2+ coordination environments in 234 oxysalts and 75 minerals will be summarized. 

These data and more recent results on several multinary copper oxides are presented below. 

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