Tetraaquabis(nicotinamide-kappa N-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 Ni-II 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 angstrom, 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)degrees, while the pyridine and benzene rings are oriented at a dihedral angle of 8.31 (4)degrees. In the crystal structure, O-H center dot center dot center dot O, N-H center dot center dot center dot O, C-H center dot center dot center dot O, and C-H center dot center dot center dot F hydrogen bonds link the molecules into a three-dimensional network. pi-pi Contacts between the pyridine and benzene rings [centroid-centroid distance = 3.626 (1) angstrom] may further stabilize the crystal structure. The 2-fluorobenzoate anion is disordered over two orientations, with an occupancy ratio of 0.85:0.15.