Triheteropolyanions containing copper(II), manganese(II), or manganese(III)

Triheteropolyanions XZW11O40H2n− (x = B, Zn, P, Si, Ge; Z = CuII, MnII, MnIII), XZMo11O40H2n− (X = P, Si, Ge; Z = MnII, CuII), and X2′CuW17O62H28− (X′ = P, As) are reported. All anions are degraded slowly by base; acid attack on the CuII and MnII anions is rapid, but the very stable free acids of the XMnIIIW11O40H2n− anions can be prepared. The molybdates are much less stable than the tungstates. The manganese complexes are high-spin; all salts are magnetically dilute. The Mn(II) complexes show metal-to-ligand charge-transfer bands in the near u.v. The Mn(III) 20,000 cm−1 ligand-field bands show structure which cannot be satisfactorily explained. The Mn(III)/Mn(II) redox potentials range from +0·43 V to +0·88 V.