Bis(2,2′,2′′-nitrilo­triacetamide-κ³O,N,O′)nickel(II) dinitrate tetra­hydrate

In the title compound, [Ni(C₆H₁₂N₄O₃)₂](NO₃)₂·4H₂O, the Ni^II cation is located on an inversion center and is N,O,O′-chelated by two nitrilo­tris­(acetamide) mol­ecules in a distorted octa­hedral geometry. The complex cations, nitrate anions and lattice water mol­ecules are connected by O—H...O and N—H...O hydrogen bonds, forming a three-dimensional supra­molecular structure.