Crystal structure of poly[bis-(?-nicotinamide-?(2) N (1):O)bis-(?-4-nitro-benzoato-?(2) O (1):O (1'))zinc].

ABSTRACT: The asymmetric unit of the title coordination polymer, [Zn(C7H4NO4)2(C6H6N2O)2] n , contains two 4-nitro-benzoate (NB) anions and two nicotinamide (NA) ligands. The Zn(II) atom has a slightly distorted octa-hedral coordination sphere. In the equatorial plane, it is coordinated by three carboxyl-ate O atoms of the NB anions and one O atom of one of the two NA ligands. The axial positions are occupied by the pyridine N atoms of the two NA ligands. In the two NB anions, the carboxyl-ate groups are twisted away from the attached benzene rings by 13.8?(2) and 13.4?(2)°, while the benzene rings are oriented at a dihedral angle of 11.5?(2)°. The dihedral angle between the NA rings is 10.3?(1)°. Only one of the two NB anions and one of the two NA ligands bridge adjacent Zn(II) ions through eight- and twelve-membered rings, respectively, forming polymeric chains running along the a-axis direction. In the crystal, N-H ? O hydrogen bonds link adjacent chains, enclosing R(16), R 2 (2)(20) and R 6 (6)(16) ring motifs, forming layers parallel to (01-1). The layers are linked via a number of C-H?O hydrogen bonds, forming a three-dimensional network.

SUBMITTER: Ask?n GS 

PROVIDER: S-EPMC4420036 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature