trans-Diaquabis(nicotinamide-N1)bis(4-nitrobenzoato-O)cobalt(II)

The title cobalt complex, [Co(C7H4NO4)2(C6H6N2O)2(H2O)2], is monomeric and centrosymmetric, and contains two water molecules, two 4-nitrobenzoate and two nicotinamide (NA) ligands, all acting as monodentate ligands. The four nearest O atoms around the Co atom form a slightly distorted square-planar arrangement, with a distorted octahedral coordination completed by the pyridine N atoms of the NA ligand at a distance of 2.134 (2) A. The water molecules are hydrogen bonded to the carboxyl O atoms [O⋯O 2.634 (5) A].