新型复合功能晶体Cd_4TbO(BO_3)_3结构与性能研究

Structure and Properties of Novel Mulit-functional Crystal Cd_4TbO(BO_3)_3

为探索新型复合功能晶体材料,采用高温固相反应法合成了Cd_4TbO(BO_3)_3多晶粉末,并以Na F-B2O3为助熔剂生长出了小晶体。结构分析表明,Cd_4TbO(BO_3)_3晶体属于单斜晶系,Cm空间群,晶胞常数为a=7.982(1)、b=15.806(3)、c=3.487(7)、α=90°、β=100.57°、γ=90°,晶体中的阴离子基团为[BO_3]。测量了TG-DSC曲线、紫外可见透过光谱、红外光谱、拉曼光谱,并计算了晶体单位体积Tb的含量。结果表明,Cd_4TbO(BO_3)_3晶体在500~1500 nm范围内透过率大于70%。Cd_4TbO(BO_3)_3晶体单位体积含Tb量为4.624×1021/cm3,是磁光晶体TGG单位体积含Tb量的0.3倍。综上表明Cd_4TbO(BO_3)_3是一种有前途的复合功能晶体材料。

A new cadmium-rare earth（ Tb） oxyborate Cd4TbO（BO3）3 was synthesized through hightemperature solid-state reaction in platinum crucibles and its crystal was successfully grown using Na FB2O3 as flux. Single crystal X-ray diffraction exhibits that Cd4TbO（BO3）3crystallizes in the monoclinic space group of Cm with unit cell parameters a = 7. 982（ 1）,b = 15. 806（ 3）,c = 3. 487（ 7）,α =90°,β = 100. 57°,γ = 90°. The IR and Raman spectra indicate that（ BO3） is the only anion group in the Cd4TbO（BO3）3 crystal. Furthermore, the UV-vis-NIR reflectance spectrum indicates that the transmittance of Cd4TbO（ BO3）3crystal in the range of 500-1500 nm is greater than 70%. The content of Tb is 4. 624 × 1021/cm^3 per unit volume of crystal 0. 3 times of the content of Tb per unit volume of TGG crystal,suggesting that Cd4TbO（BO3）3is a fairly promising mulit-functional crystal.