Yajuan Mu

Coordination polymers based on a flexible bis(triazole) ligand and aromatic polycarboxylate anions: syntheses, topological structures and photoluminescent properties

Four new coordination polymers, namely, {[Cd(btmx)(BTEC)0.5(H2O)]·H2O}n (1), {[Cd(btmx)1.5(1,2,4-HBTC)]·(H2O)2}n (2), {[Co(btmx)(HBTC)]·2H2O}n (3) and [Co(btmx)(1,4-BDC)]n (4) (btmx = 1,4-bis(1,2,4-triazol-1-ylmethyl)-2,3,5,6-tetramethylbenzene, H4BTEC = 1,2,4,5-benzenetetracarboxylic acid, 1,2,4-H3BTC = 1,2,4-benzenetricarboxylic acid, 1,3,5-H3BTC = 1,3,5-benzenetricarboxylic acid and 1,4-H2BDC = 1,4-benzenedicarboxylic acid) have been obtained under hydrothermal conditions and characterized structurally. Complex 1 is a 3D 3-fold interpenetrating (4,4)-connected net with (4·64·8)(42·62·82) topology. Complex 2 displays a 2D cabinet-like structure with infinite 1D double Cd–btmx chains. Complex 3 possesses a 3D 3-fold interpenetrating 4-connected framework with 66-dia topology. Complex 4 exhibits a (4,6)-connected 3D pillar-layered structure with point symbol of (44·62)(44·610·8). The structural differences of these complexes demonstrate that the flexible ligand btmx and aromatic polycarboxylate anions play critical roles in the formation of the resulting frameworks. Furthermore, the photoluminescent properties of 1 and 2 have been studied in the solid state at room temperature.

Syntheses, structures, and fluorescent properties of two helical complexes based on a long rigid N-heterocyclic ligand

A long N-heterocyclic ligand, 2,6-bis(3-(pyrid-3-yl)-1,2,4-triazolyl)pyridine (H2bptp), and Zn(II)/Pb(II) yield {[Zn(bptp)(H2O)] · 2H2O·CH3CN} n (1) and {[Pb(bptp)] · H2O} n (2). Single-crystal X-ray diffraction analysis reveals that 1 and 2 possess 2-D networks containing alternating left- and right-handed helical motifs. Topologically, 1 features a (4,4) topology, while 2 exhibits a (6,3) topology. The bptp2− in 1 and 2 adopts syn-anti and syn-syn conformations, respectively. The results indicate that the long rigid N-heterocyclic ligand can adopt different conformations to coordinate with metals, beneficial to construction of helical structures with diverse topologies. The difference between the photoluminescence properties of the two complexes reveals that metal ions and coordination environment have significant influences on photoluminescence behavior.

CCDC 878108: Experimental Crystal Structure Determination

Related Article: Yajuan Mu, Gang Han, Zhen Li, Xiaoting Liu, Hongwei Hou, Yaoting Fan|2012|Cryst.Growth Des.|12|1193|doi:10.1021/cg201180u