Synthesis of Werner- and Werner-like-type clathrates, their characterization, and theoretical calculation of their...

In this paper, the synthesis and structural characterization of three new coordination compounds in crystal structure consisting of a nickel atom, varying numbers of 3-aminopyridine molecules, and two isothiocyanate ion ligands are presented. The crystal structures of these compounds were determined by single crystal X-ray diffraction. Consequently, the explicit formulas and shorthand notations of the compounds are [Ni(NCS)₂(C₅H₆N₂)₂(H₂O)]·(H₂O) (1), [Ni(NCS)₂(C₅H₆N₂)₃]·(C₂H₆) (2), and [Ni(NCS)₂(C₅H₆N₂)₄]·2(C₅H₆N₂) (3). The consistency of the crystal structure data was confirmed by elemental analysis and infrared spectroscopy. These coordination compounds are Werner-like-type clathrates containing water, ethane, and 3-aminopyridine molecules as guest molecules in their structures, respectively. According to the single crystal X-ray diffraction analyses of the compounds, 1 and 3 appear to have a 3D supramolecular network-type crystal structure, while 2 has a 2D supramolecular network-type crystal structure. The N-H⋯O, O-H⋯N, N-H⋯S, N-H⋯N, and N-H⋯π bonds, as well as other bonds, contribute to the crystallization. In these compounds, the Ni atoms are surrounded by various ligand molecules, adopting an octahedral arrangement. To examine certain chemical and structural properties of the compounds, computational studies were made using their cif files using the program Gaussian 03. According to the calculation results, compound 2 has higher kinetic stability, lower chemical reactivity, and higher semiconductor properties than the other compounds. In addition, the UV-Vis and NMR excitation transitions of the compounds were calculated. Hirshfeld surface analyses indicate that C⋯H, O⋯H, S⋯H, H⋯H, and N⋯H interactions play the most significant role in the formation of their crystal structures.