Tetra­Aqua­Bis(Nicotinamide-Κn 1)Nickel(II) Bis­(2-Fluoro­Benzoate)

Abstract

The asymmetric unit of the title complex, [Ni(C6H6N2O)2(H2O)4](C7H4FO2)2, contains one-half of the complex cation with the NiII atom located on an inversion center, and a 2-fluoro­benzoate (FB) counter-anion. The four O atoms in the equatorial plane around the Ni atom form a slightly distorted square-planar arrangement with an average Ni—O bond length of 2.079 Å, and the slightly distorted octa­hedral coordination is completed by the two N atoms of the nicotinamide (NA) ligands in the axial positions. The dihedral angle between the carboxyl group and the attached benzene ring is 28.28 (11)°, while the pyridine and benzene rings are oriented at a dihedral angle of 8.31 (4)°. In the crystal structure, O—H⋯O, N—H⋯O, C—H⋯O, and C—H⋯F hydrogen bonds link the mol­ecules into a three-dimensional network. π–π Contacts between the pyridine and benzene rings [centroid–centroid distance = 3.626 (1) Å] may further stabilize the crystal structure. The 2-fluoro­benzoate anion is disordered over two orientations, with an occupancy ratio of 0.85:0.15.