Poly[(2,2′-bipyridyl)-μ3-cyanido-di-μ2-cyanido-dicopper(I,II)]

The title compound, [Cu-2(CN)(3)(C10H8N2)](n), crystallizes as a cyanido-bridged three-dimensional polymeric structure, where there coexist Cu-I and Cu-II ions along with mu(3)- and mu(2)-bridging cyanide groups. Each Cu-I ion is coordinated by four C atoms [Cu-C = 1.956 (3)-2.147 (3) angstrom] from two mu(3)- and two mu(2)-cyanide groups in a tetrahedral environment. The Cu-II ion is coordinated by two N atoms from the 2,2'-bipyridyl ligand and three N atoms from one mu(3)- and two mu(2)-cyanide groups in a square-pyramidal geometry [Cu-N = 1.967 (3)-2.183 (3) angstrom]. The Cu-I ions are paired by two C atoms from two cyanide groups into a dinuclear unit with a short Cu-I center dot center dot center dot Cu-I distance of 2.5398 (8) angstrom. Each dinuclear unit links six Cu-II ions by four mu(2)- and two mu(3)-cyanide groups to form a 4,6-connected framework, with Cu-I center dot center dot center dot Cu-II separations ranging from 4.864 (4) to 5.252 (4) angstrom.