Syntheses,Crystal Structures and Luminescent Properties of Two Lanthanide Coordination Polymers Based on Bifunctional Ligand

Two lanthanide coordination polymers, [Eu（HL）（L）（H2O）2]n（1） and [Tb（H0.5L）2]n（2）, based on bifunctional 5-（1H-imidazol-1-yl） isophthalic acid（H2L）, are hydrothermally synthesized and characterized by both single-crystal and powder X-ray diffraction analyses, and FT-IR. In compound 1, the basic inorganic building unit of the coordination network is the dinuclear [Eu2（COO）6] cluster. Each [Eu2（COO）6] cluster connects four HL^- ligands and each HLligand links two [Eu2（COO）6] clusters, resulting in a 2D coordination layer. The adjacent 2 D layers are further connected via neighboring inter-layer hydrogen bonds to give a 3D supramolecular structure. In compound 2, the Tb^3＋ is coordinated to six oxygen atoms. Each Tb^3＋ ion connects six ligands and each ligand links three Tb^3＋ ions, leading to a 3D coordination polymeric network which exhibits remarkably high thermal stability up to 500℃. Furthermore, due to the successful incorporation of Tb^3＋, compound 2 displays characteristic luminescent emission in the solid state at room temperature. The combination of high thermal stability and fluorescent property of compound 2 would make it as a promising light-emitting material.

Syntheses,Crystal Structures and Luminescent Properties of Two New Zinc(Ⅱ) Complexes Based on Bifunctional Ligand

By using solvothermal method,two novel coordination polymers based on 4-（4-carboxyphen-yl）-1,2,4-triazole（Hcpt） and Zn（Ⅱ） cations,[Zn（cpt）（OH）]_n·n H_2O（FJU-32） and [Zn（cpt）（atrz）]n（FJU-33）（Hatrz = 3-amino-1,2,4-triazolate）,were synthesized and characterized by single-crystal X-ray diffraction analyses,elemental analyses,FT-IR and powder X-ray diffraction. FJU-32 crystallizes in monoclinic,space group P21/c with a = 3.7441（3）,b = 23.0384（19）,c = 11.8562（10） ？,β = 99.069（8）o,V = 1009.91（15） ？3,Dc = 1.898 g/cm3,C_9H_9N_3O_4Zn,Mr = 288.57,F（000） = 916,μ（MoKα） = 2.439 mm^（-1）,Z = 4,R = 0.0600 and wR = 0.1306 for 2412 observed reflections（I 〉 2σ（I））,and R = 0.0704 and wR = 0.1349 for all data. FJU-33 crystallizes in monoclinic space group P21/c with a = 12.7483（5）,b = 9.9922（3）,c = 9.8403（3） ？,β = 100.756（4）°,V = 1231.47（7） ？~3,Dc = 1.816 g/cm^3,C_（11）H_9N_7O_2Zn,Mr = 336.62,F（000） = 680,μ（Cu Kα） = 2.957 mm^（-1）,Z = 4,R = 0.0478 and w R = 0.1184 for 2466 observed reflections（I 〉 2σ（I））,and R = 0.0687 and w R = 0.1309 for all data. In FJU-32,Zn（Ⅱ） is coordinated to three μ3-OH groups forming an unprecedented 1D zigzag-like double chain,and the 1D double chains are connected to four neighbouring double chains by the cpt ligands to form an extended 3D porous coordination polymer. In FJU-33,the adjacent [Zn（atrz）] 2D layers are further connected by the cpt ligands via Zn–O coordinated bonds and neighboring interlayer hydrogen-bonding interactions to give rise to an overall 3D pillared layer structure. The neutron triazole group of the cpt ligand has weaker coordination ability than the triazolate anion of atrz ligand. Furthermore,FJU-32 and FJU-33 display high thermal stability up to 300 ℃,and the solid state fluorescence reveals that two new complexes are potential optical materials.