新型三维开放骨架稀土硫酸盐[Ln4(H2O)4(SO4)(10)](C4N2H(12))4(H2O)4(Ln=Gd,Eu)的合成、结构及荧光性质

Synthesis,Characterization and Fluorescent Properties of Two 3D Open-framework Rare-earth Sulfates [Ln_4(H_2O)_4(SO_4)_(10)](C_4N_2H_(12))_4(H_2O)_4(Ln=Gd,Eu)

以哌嗪为模板剂,在水-乙醇混合溶剂体系中以溶剂热法合成了2个具有三维开放骨架结构的稀土硫酸盐[Ln4(H2O)4(SO4)10](C4N2H12)4(H2O)4[Ln=Gd(1),Eu(2)],并对其进行了结构表征、热重以及荧光光谱分析.单晶结构解析表明,化合物1和2属于异质同构,均属单斜晶系,P21/c空间群,化合物1:a=1.9691(3)nm,b=1.9249(3)nm,c=1.3186(2)nm,β=92.33(0)°,V=4.9935(1)nm3,Z=4.化合物2:a=1.9723(8)nm,b=1.9279(8)nm,c=1.3210(5)nm,β=92.329(1)°,V=5.0187(3)nm3,Z=4.2个化合物在ab平面上由SO4,GdO8和GdO9多面体共边或共角交错连接形成含有八元环和十六元环的二维层状结构,该二维层沿c方向平行排列,相邻层通过SO4四面体相连形成具有孔道的三维开放骨架结构,其孔道中包含平衡骨架负电荷的质子化哌嗪分子.化合物2的固体荧光光谱分析显示,其在397 nm激发波长下表现出典型的Eu3+发光性质.

Two novel 3D open framework rare-earth sulfates,[Ln4（H2O）4（SO4）10]（C4N2H12）4（H2O）4[Ln=Gd（1）;Eu（2）]were solvothermally synthesized in a water-ethanol mixed solvent system using piperazine as the template and characterized by single-crystal X-ray diffraction.The two compounds are isostructural and crystallize in the monoclinic system,space group P21/c with unit cell parameters of a=1.9691（3） nm,b=1.9249（3） nm,c=1.3186（2） nm,β=92.33（0）°,V=4.9935（1） nm3,Z =4 for compound 1,and a=1.9723（8） nm,b=1.9279（8） nm,c=1.3210（5） nm,β=92.329（1）°,V=5.0187（3） nm3,Z=4 for compound 2,Both compounds consist of 2D sheets of 8-membered rings and 16-membered rings con-structed from edge-or corner-sharing SO4,GdO8 and GdO9 polyhedra.The 2D sheets stack parallel with each other and are pillared by SO4 tetrahedra to form a 3D open framework,in which the protonated piperazine molecules are located to balance the negative charges of the framework.The solid-state fluorescence spectra of compound 2 show the characteristic luminescent behavior of Eu^3＋ ions.