metal-organic compounds
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In the title compound, [Cu(C5H3N2O2)2(H2O)2], the CuII 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—HO 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—HO hydrogen bonds between the water molecules and the coordinating carboxylate O atoms. Weak C—HO 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.