Bis(mu-2-fluorobenzoato-1:2 kappa O-2:O ')(2-fluorobenzoato-1 kappa O-2,O ')(2-fluorobenzoato-2 kappa O)dinicotinamide-1 kappa N-1,2 kappa N-1-dizinc(II)-2-fluorobenzoic acid (1/1)

Abstract

The asymmetric unit of the title compound, [Zn-2(C7H4FO2)(4)(C6H6N2O)(2)]center dot C7H5FO2, consists of a binuclear Zn-II complex bridged by two carboxyl groups of 2-fluorobenzoate (FB) anions and a 2-fluorobenzoic acid molecule. The two bridging FB anions, one chelating FB anion and one nicotinamide (NA) ligand coordinate to one Zn cation with a distorted square-pyramidal geometry, while the two bridging FB anions, one monodentate FB anion and one NA ligand coordinate to the other Zn cation with a distorted tetrahedral geometry. Within the binuclear molecule, the pyridine rings are oriented at a dihedral angle of 19.41 (14)degrees. In the crystal structure, the uncoordinated 2-fluorobenzoic acid molecules are linked by O-H center dot center dot center dot O hydrogen bonding, forming centrosymmetric supramolecular dimers. Intermolecular N-H center dot center dot center dot O hydrogen bonds link the complex molecules into a three-dimensional network. The pi-pi contacts between nearly parallel pyridine and benzene rings [dihedral angles of 19.41 (14) and 12.72 (16)degrees, respectively, centroid-centroid distances = 3.701 (2) and 3.857 (3) angstrom] may further stabilize the crystal structure. The fluorine atoms in two FB ligands are disordered over two positions, with occupancy ratios of 0.70:0.30.