系列Ln(Ⅲ)配聚物的合成、结构及近红外发光性能

Syntheses,Structures and Near Infrared Luminescence of a Series of Ln(Ⅲ) Coordination Polymers

通过水热反应合成5种结构新颖的配聚物:{[Ln_2(1,3-bdc)_3(H_2O)_4](DMF(H_2O}_n[Ln=Pr(1),Nd(2),Gd(3)]和{[Ln_4(1,3-bdc)_6(H_2O)_4(DMF)](DMF(2H_2O}_n[Ln=Er(4),Ho(5)](1,3-bdc:间苯二甲酸,DMF:N,N-二甲基酰胺)。通过单晶X射线衍射、红外光谱、紫外-可见-近红外(UV-Vis-NIR)光谱、荧光光谱等技术手段对产物的结构和性能进行了表征。结果表明,配聚物1~3是同构的,属单斜晶系,P2(1)/n空间群;配聚物4、5是同构的,属三斜晶系,P-1空间群。在晶体中,间苯二甲酸根采用多样的配位模式,使配聚物呈现多维的结构。除配聚物4,其余均呈现Ln(Ⅲ)的特征NIR发光,并与其UV-Vis-NIR吸收光谱相关联。

Five novel Ln （ Ⅲ ） coordination polymers, { [ Ln2 （1,3-bdc） 3 （ H2 O）, ] （ DMF （ H2 O } n （ Ln = Pr（1）, Nd（2）, Gd（3）） and {[Ln4（1,3-bdc）6（H2O）4（DMF）]（DMF（2H2O }n（Ln =Er（4）, Ho（5）） （1,3-bdc = isophthalic acid, DMF = N, N-dimethyl formamide）, have been synthesized by hydrothermal methods and characterized by single-crystal X-ray diffraction, infrared spectroscopy （IR）, ultraviolet-visible-near infrared（UV-Vis-NIR） and fluorescence spectroscopy. The results show that coordination polymers 1 to 3 are isomorphous and crystallized in the monoclinic with space group P2 （1）/n, and coordination polymers 4 and 5 are isomorphous and belong to the triclinic system with space group P-1. Polymers present multidimensional structures due to versatile coordination modes of 1,3-bdc2- in crystals. Except for coordination polymer 4, others exhibit NIR luminescent properties that are associated with UV-Vis-NIR absorption spectra.