LnBaB_9O_(16)∶Eu^(3+)(Ln=La,Y)的结构与荧光性质  

Structural and Luminescent Properties of LnBaB_9O _(16)∶Eu ^(3+)(Ln=La,Y)

作　　者：杨智[1] 林建华[1] 苏勉曾[1] 尤力平[2] 王渭 陶冶 

机构地区：[1]北京大学稀土材料化学及应用国家重点实验室,北京100871 [2]北京大学电子显微镜实验室,北京100871 [3]北京高能物理研究所同步辐射实验室,北京100039

出　　处：《高等学校化学学报》1999年第12期1832-1837,共6页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金!(批准号:29625101)

摘　　要：利用电子衍射、X射线衍射和荧光光谱等方法研究了 L n Ba B9O16(L n=L a,Y)的结构特性 .L n Ba B9O16为单斜晶系 ,其中 L a Ba B9O16的晶胞参数 a=1.36 6 0 nm,b=0 .7882 nm,c=1.6 2 53nm,β=10 6 .15°;YBa B9O16的晶胞参数 a=1.3476 nm,b=0 .7776 nm,c=1.6 0 4 0 nm,β=10 6 .38°.荧光光谱研究表明 ,这两种化合物结构不同 ,Y3 +在 YBa B9O16结构中处于中心对称格位 ,而 L a Ba B9O16中 L a3 +的格位则无中心对称性 .Gd3 +部分取代 L a Ba B9O16∶ Eu3 +中的 L a3 +可改善 Eu3 +离子的发光性质 .L a Ba B9O16∶ Eu3 +在真空紫外区的吸收比较弱 ,这可能与硼氧比较小有关 .Structural properties of LnBaB 9O 16 (Ln=La, Y) were investigated by means of X ray powder diffraction, electron diffraction and luminescence. These compounds crystallize in the monoclinic crystal system with lattice parameters a =1.366 0 nm, b =0.788 0 nm, c =1.625 3 nm and β =106.15° for LaBaB 9O 16 and a =1.347 6 nm, b =0.777 6 nm, c =1.604 0 nm and β = 106.38° for YBaB 9O 16 . The study of luminescence spectra of Eu 3+ doped materials reveals that the structures of these two compounds are different. The local symmetry of the rare earth ions is central symmetric in YBaB 9O 16 and non central symmetric in LaBaB 9O 16 . The emission intensity of LaBaB 9O 16 ∶Eu 3+ is enhanced by partial substitution of La 3+ with Gd 3+ . Absorption of LaBaB 9O 16 ∶Eu 3+ in the VUV region is relatively weak, which may be related to the small ratio of B∶O.

关 键 词：硼酸盐 电子衍射 X射线衍射 荧光光谱 稀土 

分 类 号：O613.81[理学—无机化学] O611.65[理学—化学]