Tetra­aqua­bis­(pyridine-3-carbo­nitrile-κN (1))nickel(II) benzene-1,4-di­carboxyl­ate tetra­hydrate

A nickel(II) terephthalate complex, viz. [Ni(C(6)H(4)N(2))(2)(H(2)O)(4)](O(2)CC(6)H(4)CO(2))·4H(2)O, has been synthesized and studied by single-crystal X-ray diffraction. It crystallizes in the triclinic space group P [Image: see text]. The crystal structure shows an approximately octa­hedral coordination environment of the complex with the [Ni(H(2)O)(4)(3-NCpy)(2)](2+) (3-NCpy is pyridine-3-carbo­nitrile) cation associated with four free water mol­ecules and hydrogen bonded to a terephthalate dianion [graph set R (2) (2)(8)]. The supra­molecular structure of the compound is stabilized by a three-dimensional array of O—H⋯O and O—H⋯N hydrogen bonds, along with π–π stacked pyridine-3-carbo­nitrile rings and C—H⋯O inter­actions.