A three-dimensional supramolecular network built with the zigzag chain complex bis(5-carboxy-1 H-imidazole-4-carboxylato)copper(II)

In the title complex, poly[copper(II)-di-μ-5-carboxy-1H-imidazole-4- carboxylato], [Cu(C₅H₃N₂O₄) ₂]_n or [Cu(H₂-Imda)₂]_n, each imidazole moiety is bonded to the Cu atom via O and N atoms to give a square-planar coordination [Cu-O = 2.014(2) and 2.016 (2) Å, and Cu-N = 1.982(3) and 1.992 (2) Å]. The distorted square-pyramidal geometry at the Cu atom results from coordination to an adjacent O atom [Cu-O = 2.305 (2) A], which generates zigzag chains. There is a sixth, weaker, octahedral coordination to the Cu atom from an inversion-related O atom [Cu-O = 3.090 (2) A], which links the chains into sheets in the (100) plane. Imidazole moieties in the sheets are linked in the [100] direction by pairs of N-H⋯O and C-H⋯O hydrogen bonds, thus generating a three-dimensional network.