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Updated: Apr 12, 2026
Synthesis and Characterization of Functionalized Metal-organic Frameworks
Published on: September 5, 2014
Crystal structure of poly[bis-(μ-nicotinamide-κ(2) N (1):O)bis-(μ-4-nitro-benzoato-κ(2) O (1):O (1'))zinc]
Gülçin Şefiye Aşkın1, Hacali Necefoğlu2, Ali Murat Tonbul2
1Department of Physics, Hacettepe University, 06800 Beytepe, Ankara, Turkey.
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.
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