Synthesis, crystal structure, fluorescence properties, and theoretical studies of a dinuclear Ni(II) complex derived from a quinoline-containing half-salamo-type ligand

A quinoline-containing semi-salamo-type ligand, HL, was synthesized and a dinuclear Ni(II) complex, [Ni-2(L)(2)(NCS)(2)], was produced. The complex was experimentally analyzed by elemental analysis, fluorescence, and UV-Vis spectroscopy. X-ray single crystal diffraction experiments showed that the complex is a six-coordinate, structurally symmetric, phenoxy-bridged dinuclear Ni(II) dimer with the participation of SCN(- )in the coordination to satisfy charge neutrality. The self-assembly forms a 2-D supramolecular network structure through hydrogen bonding and pi center dot center dot center dot pi interactions. DFT calculations were performed on the complex to analyze its energy gaps, and UV-Vis experiment was verified by TD-DFT calculation. In addition, close intermolecular contacts were investigated by Hirshfeld surface analysis to quantify the crystal structure interaction.