Synthesis, crystal structure and magnetic properties of an octacyanometallate-based 3-D CuII–WIV bimetallic assembly

The three-dimensional cyano-bridged bimetallic coordination polymer, [Cu(L)]2[W(CN)8] · 4H2O (L = 3,10-diethanol-1,3,5,8,10,12-hexaaza-cyclotetradecane) 1, has been synthesized and characterized. X-ray study shows that the asymmetric unit of the three-dimensional Cu(II)–W(IV) polymeric assembly consists of four crystallized water molecules, two [Cu(L)]2+ cations and one [W(CN)8]4− anion. The CuII centers in compound 1 exhibit elongated octahedral geometries, while the WIV centers adopt distorted square antiprism geometries. Each WIV coordinated via four cyano groups to four CuII. The structure of compound 1 can be described as an infinite 3-D assembly of W⋯Cu⋯W linkage. The thermal and magnetic behavior of this compound has been investigated. Variable-temperature magnetic susceptibility measurements reveal that there is a weak antiferromagnetic interaction between the CuII centers in compound 1.