含Sm(Ⅲ)配聚物的合成、结构及发光性能

Synthesis,structure and luminescent property of Sm(Ⅲ)coordination polymer

采用水热合成的方法,合成了配聚物{[Sm(2,5-pydc2-)(Ac-)·H2O]·2H2O}n(2,5-pydc2-=吡啶-2,5-二羧酸,HAc=醋酸),通过X射线单晶衍射仪确定了配聚物的晶体结构.结构分析表明,该配聚物是单斜晶系,Pn空间群,晶胞参数为:a=9.381 6(9)nm,b=8.3519(8)nm,c=16.8596(16)nm,β=106.213(5)°.在室温下测定了配聚物固态粉末的IR光谱,UV-Vis-NIR光谱以及荧光激发和发射光谱,并进行了分析指认.重点讨论了它们的发光性质,尤其是配聚物在NIR区表现出Sm(Ⅲ)的特征发射.发现配聚物中Sm(Ⅲ)离子在近红外区的发射带对比理论发射带出现了明显的红移和劈裂.这些可能是由于配聚物中第二配体的引入,改善了Sm(Ⅲ)离子的发光,协调了Sm(Ⅲ)离子的能级,使6 FJ(J=3/2,5/2,7/2)能级升高和劈裂的结果.

A coordination polymer, {[Sm（2,5-pydc^2- ）（Ac^ -） · H2O] · 2H2O}n（2,5-pydc^2- =Pyridine-2,5-diearboxylic acid, HAc= acetic acid ）, has been synthesized by the hydrothermal method. The structure was determined by single-crystal Xray diffractometer. The complex crystallizes in the Monoclinic system, space group Pn with a=9. 3816（9）nm,b=8. 3519（8）nm,c=16. 859 6（16）nm, β =106. 213（5）°. At room temperature in the solid state, the IR, UV-Vis-NIR and fluorescence excitation and emission spectra of the complex were measured and analyzed. The luminescent properties of the complex are discussed emphatically, and the complex shows characteristic emissions of the Sm（Ⅲ） ion in the NIR region. Comparing with theory emission band, the near infrared emission band of Sm（ Ⅲ ） ion in complex shows obvious red shift and splitting. These may be due to the introduction of the second ligand to the complex, which improved the emitting and coordinated the energy level of Sm（Ⅲ） ion, resulting the level of ^6FJ（J=3/2, 5/2, 7/2） to rise and splitting.