Diaqua­bis(1,3-propane­diamine)nickel(II) squarate tetrahydrate

The asymmetric unit of the title compound, [Ni(C(3)H(10)N(2))(2)(H(2)O)(2)](C(4)O(4))·4H(2)O, contains one-half of the diaqua­bis(1,3-propane­diamine)nickel(II) cation, one-half of the centrosymmetric squarate anion and two uncoordinated water mol­ecules. In the cation, the Ni(II) atom is located on a crystallographic inversion centre and has a slightly distorted octa­hedral coordination geometry. The six-membered chelate ring adopts a chair conformation. O—H⋯O hydrogen bonds link the cation and anion through the water mol­ecule, while N—H⋯O hydrogen bonds link the cation and anion and cation and water mol­ecules. In the crystal structure, inter­molecular O—H⋯O and N—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional network structure.