2017. 58, 1 – UDC 548.73:541.49:546.47 ZINC HALIDE COMPLEXES OF THIONICOTINAMIDE; CRYSTAL STRUCTURE OF DICHLORIDO BIS(THIONICOTINAMIDE-xN)ZINC(II) M. Akhtar1, M.R. Malik1, M.N. Tahir2, S. Nadeem1, M. Altaf3 , M. Sohail3, S. Ali1, S. Ahma d 4 1Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan 2Department of Physics, University of Sargodha, Sargodha, Pakistan 3Center of Excellence in Nanotechnology, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia 4Department of Chemistry, College of Sciences and Humanities, Prince Sattam bin Abdulaziz University, Al-Kharj, Saudi Arabia E-mail: saeed_a786@hotmail.com Received March, 13, 2016 Zinc halide complexes of thionicotinamide (TNA) having the general formula [Zn(TNA)2X2] (X = Cl–, Br–, I–) are prepared and characterized by thermal analysis, IR and NMR spectroscopy. <...> The crystal structure of one of them, dichloridobis(thionicotinamide-xN)zinc(II), [Zn(TNA)2Cl2 ] (1), is determined using X-ray crystallography. <...> In 1, the zinc atom is coordinated by two thionicotinamide ligands through nitrogen atoms and two chloride ions in a distorted tetrahedral coordination environment. <...> The molecular structure of the complex is stabilized through intermolecular hydrogen bonding. <...> The Zn+2 ion is known to have a high affinity towards nitrogen and sulfur donor ligands, as demonstrated by a considerable body of knowledge on Zn(N,S-ligands) complexes [ 1—10]. <...> Heterocyclic thiones possessing a combination of soft sulfur and hard nitrogen donor atoms are among the ligand systems used to mimic bio-relevant metal-sulfur interactions [11—17 ]. <...> Several structural reports on zinc(II) complexes with thiones are available in the literature, which demonstrate that thiones coordinate with zinc(II) through a sulfur atom in a tetrahedral environment [19—29 ]. <...> We have previously examined the coordination behavior of thione ligands towards d10 metals with the aim of gaining more information about the structural, spectral, and biological properties of the resulting complexes [29—33 ]. <...> Herein, we report the synthesis and spectral studies of three zinc(II) complexes of thionicotinamide (TNA) and the crystal structure of one of them, [Zn(TNA)2Cl2]. <...> The title complex [Zn(TNA)2Cl2 <...>