Synthesis, crystal structure and Hirshfeld surface analysis of a 1D coordination polymer catena-poly[[di­aqua­bis­(nicotinamide-κN (1))nickel(II)]-μ-fumarato-κ(2) O (1):O (4)]

The reaction of NiCl(2) with fumaric acid and nicotinamide in basic solution produces the title polymeric complex, [Ni(C(4)H(2)O(4))(C(6)H(6)N(2)O)(2)(H(2)O)(2)](n). The Ni(II) cation, located on an inversion centre, is coordinated by two O atoms of the fumarate dianions, two N atoms from nicotinamide ligands and two water mol­ecules in a distorted octa­hedral fashion. In the crystal, the fumarate dianions bridge the Ni(II) cations, forming polymeric chains propagating along the [101] direction; the polymeric chains are further linked by O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds, forming a three-dimensional supra­molecular architecture. Hirshfeld surface analyses and two-dimensional fingerprint plots were used to analyse the inter­molecular inter­actions present in the crystal, indicating that the most important contributions for the crystal packing are from H⋯O/O⋯H (35.9%), H⋯H (31.7%) and C⋯C (10.4%) inter­actions.