Hydrothermal syntheses, crystal structures and topological analyses of four new 3D coordination polymers with mixed ligands

Four new coordination polymers, namely [Ni-1.5(L)(fum)(0.5)(mal)(H2O)]center dot 4H(2)O (1), [Zn-2(L)(male)(2)]center dot 3H(2)O (2), [Ni(L)(adi)(0.5)(H2O)]center dot 0.5(adi)center dot 2.5H(2)O (3), and [Zn-2(L)(adi)(2)]center dot 5H(2)O (4) (L, tetrakis(imidazol-1-ylmethyl) methane; fum, fumarate; mal, malate; male, maleate; adi, adipate) have been synthesized under hydrothermal condition and characterized by elemental analysis, IR, and single-crystal X-ray diffraction. In compound 1, the L, fum, and mal connect the Ni(II) atoms to form a three-dimensional framework. Topologically, the compound shows a trinodal (3,4)-connected (4.10(2))(4(2).8(2).10(2))(4(2).8(4)) net. Interestingly, the fum and mal came from the configuration transformation and addition reaction of maleate during the synthesis, respectively. In compound 2, the L ligands link the Zn(II) centers to generate a 2D layer, which are further connected by the male ligands to furnish a 3D chrial 4-connected (3.7(5)) net. In compound 3, the adi ligands and the L ligands link the Ni(II) centers to form a 3D framework. Topologically, compound 3 displays a (4,5)-connected net with the Schlafli symbol of (4(2).5(2).6(2))(4(2).5(3).6(4).7). In compound 4, the L and adi ligands link the binuclear Zn(II) clusters to yield an intricate 3D (3,6)-connected net with the Schlafli symbol of (4.6(2))(4(3).6(12)). The fluorescence and thermal stability of complexes 1-4 have also been investigated. (C) 2011 Elsevier B. V. All rights reserved.