2,2-联吡啶-6,6-二羧酸与稀土配合物的合成及性能

Synthesis,Structure and Luminescence Property of Lanthanide（Ⅲ） Complexes with 2,2′-Bipyridine-6,6′-dicarboxylic Acid Ligand

利用2,2-联吡啶-6,6-二羧酸作为配体,合成了稀土配合物[Ln 2(bpydc)3·3H 2O]·H 2O·3CH 3OH(1,Ln=Eu,Tb,Yb,Gd;Hbpydc=2,2-联吡啶-6,6-二羧酸)。使用单晶X射线衍射仪、傅里叶红外光谱、紫外吸收光谱、荧光光谱以及磷光光谱等对其进行了表征和配体与发光中心的能级匹配程度的测定,探讨了配合物的荧光性能与能量传递效率。结果表明:配合物具有两种不同环境的配位中心,促使配合物在空间上具有层状堆积结构;Eu(Ⅲ)与Tb(Ⅲ)配合物分别在612与548nm处有强烈的红色与绿色荧光发射,特征荧光敏化效果明显;配体三重态能级26666cm-1与稀土离子Eu 3+(5D 0,17300cm-1)、Tb 3+(5D 4,20500cm-1)最低激发态能级匹配,存在明显天线效应,具有优良的能量传递效率。

A series of new lanthanide complexes[Ln 2(bpydc)3·3H 2O]·H 2O 3CH 3OH(1,Ln=Eu,Tb,Yb,Gd;Hbpydc=2,2′-bipyridine-6,6′-dicarboxylic acid)were synthesized with a 2,2′-bipyridine-6,6′-dicarboxylic acid(Hbpydc)ligand,and then characterized by single crystal X-ray diffraction,Fourier transform infrared spectroscopy,ultraviolet absorption spectra,fluorescence spectra and phosphorescence spectra.Results of single crystal X-ray diffraction show that the structure of the complex is based on two metal centers,which are coordinated with three ligands in total to form a layered crystal structure.Spectral analysis indicates that the complexes of Eu(Ⅲ)and Tb(Ⅲ)show intense character emission peaks at 612nm and 548nm respectively in the fluorescence spectra;the calculated triplet energy level of ligand(26666cm-1)is favorable for energy transfer into those of Eu(Ⅲ)(5D 0,17300cm-1)and Tb(Ⅲ)(5D 4,20500cm-1);obvious“antenna effect”and efficient energy transfer between the ligand Hbpydc and lanthanide acceptors are found.