trans-Di­aqua­bis­(pyridazine-3-carboxyl­ato-κ(2) N (2),O)copper(II)

In the title compound, [Cu(C(5)H(3)N(2)O(2))(2)(H(2)O)(2)], the Cu(II) ion, located on an inversion center, exhibits an octa­hedral coordination geometry. The equatorial plane is defined by two trans-related N,O-bidentate pyridazine-3-carboxyl­ate ligands and the axial positions are occupied by two water mol­ecules. In the crystal, mol­ecules are connected by O—H⋯O hydrogen bonds between the water mol­ecules and the noncoordinating carboxyl­ate O atoms, forming layers parallel to the bc plane. The layers are stacked along the a axis by further O—H⋯O hydrogen bonds between the water mol­ecules and the coordinating carboxyl­ate O atoms. Weak C—H⋯O hydrogen bonds are also observed between the pyridazine rings and the water mol­ecules and between the pyridazine rings and the non-coordinating carboxyl­ate O atoms.