Syntheses, structures and photoluminescence properties of cadmium(II) and zinc(II) complexes with pyridinylcarboxamide-containing ligand

Four new coordination complexes [Cd(DPBA-3)(2)(H2O)(2)](ClO4)(2)center dot 2H(2)O (1), [Cd(DPBA-3)(DMF)(NO3)(2)]center dot DMF (2), [Cd-3(DPBA-3)(2)(SCN)(6)]center dot 2DMF center dot 4H(2)O (3) and [Zn(DPBA-3)(SCN)(2)] (4) [DPBA-3 = N,N'-di(pyridin-3-yl) pyridine-3,5-dicarboxamide] have been synthesized and characterized by elemental analysis, IR and single crystal X-ray diffraction. Complexes 1, 3 and 4 exhibit three different types of one-dimensional (1D) chain structures constructed by the metal ions and DPBA-3 ligands, and the Cd(II)-DPBA-3 1D chains in 3 are further linked by bridging SCN ligands to afford a three-dimensional (3D) framework. Complex 2 possesses a (6,3) two-dimensional (2D) layer structure. In 1-4, the hydrogen bonds involving the amide groups play important role to stabilize the resultant frameworks. The photoluminescence properties of the DPBA-3 and the complexes were studied in the solid state at room temperature. (C) 2011 Elsevier B. V. All rights reserved.