catena-Poly[[[(5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-aza-cyclo-tetra-decane-κ(4)N)nickel(II)]-μ-oxido-[dioxidotungstate(VI)]-μ-oxido] tetra-hydrate].

In the title compound, {[NiWO(4)(C(16)H(36)N(4))]·4H(2)O}(n), the Ni(II) ion lies on an inversion center and is octahedrally coordinated by four N atoms of the tetradentate macrocyclic 5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-aza-cyclo-tetra-decane (L) ligand in the equatorial plane and two O atoms of [WO(4)](2-) anions in axial positions. Each [WO(4)](2-) anion bridges two adjacent [NiL](2+) cations, forming a chain along [001]. The chains are further connected via N-H⋯O, O-H⋯O and C-H⋯O hydrogen-bonding inter-actions, generating a three-dimensional structure.