Combination of lacunary polyoxometalates and high-nuclear transition metal clusters under hydrothermal conditions. 3. Structure and characterization of [Cu(enMe)2]2{[Cu(enMe)2(H2O)]2[Cu6(enMe)2(B-a-SiW9O34)2]}.4H2O.

Combination of lacunary polyoxometalates and high-nuclear transition metal clusters under hydrothermal conditions. 3. Structure and characterization of [Cu(enMe)2]2{[Cu(enMe)2(H2O)]2[Cu6(enMe)2(B-a-SiW9O34)2]}.4H2O.