Discrete water clusters in tetra-μ-cyanido-tetra-cyanidobis(1,4,7-triisopropyl-1,4,7-triaza-cyclo-nona-ne)dicopper(II)dinickel(II) tetra-hydrate.

The title tetra-cyanido-nickelate-copper complex, [Cu₂Ni₂(CN)₈(C₁₅H₃₃N₃)₂]·4H₂O, was synthesized by self-assembly using potassium tetracyanidonickelate(II) and dichlorido(1,4,7-triisopropyl-1,4,7-triazacyclononane)copper(II). The asymmetric unit contains half of a complex mol-ecule and two water mol-ecules. The entire complex has -1 symmetry and contains Ni(II) in a slightly distorted square-planar and Cu(II) in a square-pyramidal coordination environment. The crystal packing shows a discrete tetra-mer water cluster. Within the cluster, the four water mol-ecules are fully coplanar and each water monomer acts both as single O-H⋯O and O-H⋯N hydrogen-bond donor and acceptor.