4个Cd(Ⅱ)配位聚合物:辅助配体对晶体结构以及荧光性能的影响

采用溶剂热的方法，将配位模式丰富的多羧酸有机配体5-（2-硝基-4-羧基苯氧基）-间苯二甲酸（H₃ncpoi）与Cd²⁺离子以及不同的辅助配体原位组装而成4个新的配位聚合物晶体：[Cd（Hncpoi）（2，2''-bpy）（H₂O）]_n（1），{[Cd₂（Hncpoi）₂（bpyp）（H₂O）₄]·3H₂O}_n（2），{[Cd₂（Hncpoi）₂（azpy）（H₂O）₂]·2H₂O}_n（3），{[Cd₂（Hncpoi）₂（dpe）（H₂O）₂]·2H₂O}_n（4），其中H₃ncpoi为5-（2-硝基-4-羧基苯氧基）-间苯二甲酸，2，2''-bpy为2，2''-联吡啶，bpyp为1，4-二-吡啶基-4-亚甲基-哌嗪，azpy为4，4''-偶氮吡啶，dpe为1，2-二-（4-吡啶基）乙烯。对4个配合物进行了X射线单晶衍射、粉末衍射，元素分析、热重、荧光光谱等表征。X射线单晶结构分析表明，配合物1，2具有一维链状结构，而配合物3，4则具有二维（4，4）格子层状结构，一维链和二维层之间通过分子间作用力连接成三维超分子结构。进一步研究表明，辅助配体的构型、配位方式等对晶体结构具有决定性作用。与此同时，对几个配合物的荧光光谱进行分析，发现不同的辅助配体对配合物的荧光性能有着显著的影响。

Four Cadmium-Organic Coordination Polymers:Influence of Secondary Ligands to Crystal Structure and Luminescent Properties

Four cadmium-organic coordination polymers, namely[Cd(Hncpoi)(2,2''-bpy)(H₂O)]_n (1), {[Cd₂(Hncpoi)₂(bpyp)(H₂O)₄]·3H₂O}_n (2), {[Cd₂(Hncpoi)₂(azpy)(H₂O)₂]·2H₂O}_n (3), {[Cd₂(Hncpoi)₂(dpe)(H₂O)₂]·2H₂O}_n (4), have been solvothermally constructed from multi-carboxylic organic ligand 5-(2-Nitro-4-carboxyphenoxy)-isophthalic acid(H₃ncpoi), Cd²⁺ ions, and different auxiliary ligands:2,2''-bipyridyl(2,2''-bpy), 1,4-bis-(4-pyridylmethyl)piperazine(bpyp), 4,4''-azopyridine (azpy) and 1,2-di(4-pyridyl)ethylene(dpe), respectively. These complexes were further characterized by single-crystal X-ray diffraction, PXRD, elemental analysis, and TG. Single-crystal X-ray diffraction showed that complexes 1 and 2 exhibit 1D chain-like structure, and complexes 3 and 4 are 2D (4,4) grid layered structure. 1D chains or 2D layers of these complexes further assemble to 3D supramolecular architectures via intermolecular interactions. The coordination modes and configurations of secondary ligands have a crucial influence to the crystal structures of these complexes. Meanwhile, the photoluminescent properties of these complexes were also studied. The results showed that there are close relationship between the secondary ligands and photoluminescence properties of these coordination polymers.