Hydrothermal syntheses, crystal structures and luminescence properties of zinc(II) coordination polymers constructed by bifunctional 4′-(4-carboxyphenyl)-3,2′:6′,3"-terpyridine

Four polymeric frameworks, [Zn(cptpy)(2)(Hcptpy)(2)]center dot 2H(2)O (1), [Zn(cptpy)Cl](n) (2), [Zn-4(cptpy)(2)(3-btc)(2)](n). nH(2)O (3) and [Zn-2(cptpy)(2-btc)](n) (4), (Hcptpy = 4'-(4-carboxyphenyl)-3,2':6',3"-terpyridine, H-3(3-btc) = 1,3,5-benzenetricarboxylic acid, H-3(2-btc) = 1,2,4-benzenetricarboxylic acid) have been hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction analyses. Compound 1 has a mononuclear structure, while 2 shows a one-dimensional ladder chain containing 28 member rings with (cptpy)(-) anions as bridges. For compounds 1 and 2, weak hydrogen bonding and intra- and/or inter-molecular pi center dot center dot center dot pi stacking interactions link the mononuclear or infinite chain structures into high-dimensional supramolecular structures. Compound 3 reveals a (4,4,4)-connected three-dimensional (3D) framework. Compound 4 is a three dimensional network structure comprised of new tetranuclear zinc clusters, exhibiting a {4.6.8}{4(2).6.8(3)}{4(2).6(2).8(2)}{4(3).6(2).8(5)) topological structure. In addition, the thermal stabilities and photoluminescence properties of 1-4 were also studied. (c) 2012 Elsevier Ltd. All rights reserved.