Versatile thiomolybdate(thiotungstate)–copper–sulfide clusters and multidimensional polymers linked by cyanides

Cyanide (CN) assumes a unique role in the development of coordination chemistry, with the first CN-based coordination polymer dye Prussian blue as a milestone example. In this review, we discuss the structures of a rich class of Mo(W)–Cu–S clusters, cluster-based oligomers, 1D, 2D and 3D coordination polymers bearing CN ligands. The stable Mo(W)–Cu–S cluster skeletons in conjugation with the strong Cu–CN linkages offer enhanced stability of these cluster species, making them good nonlinear optical materials.