新型复合功能晶体Cd4TbO(BO3)3结构与性能研究

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Cd4TbO(BO3)3多晶粉末,并以NaF-B2O3为助熔剂生长出了小晶体.结构分析表明,Cd4TbO(BO3)3晶体属于单斜晶系,Cm空间群,晶胞常数为a=7.982(1) (A)、b=15.806(3) (A)、c=3.487(7) (A)、α=90°、β=100.57°、γ=90°,晶体中的阴离子基团为BO3].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, Cd4TbO(BO3)3晶体在500~1500 nm范围内透过率大于70;.Cd4TbO(BO3)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Cd4TbO(BO3)3是一种有前途的复合功能晶体材料.

Structure and Properties of Novel Mulit-functional Crystal Cd4TbO(BO3)3

A new cadmium-rare earth (Tb) oxyborate Cd4TbO(BO3)3 was synthesized through high-temperature solid-state reaction in platinum crucibles and its crystal was successfully grown using NaF-B2O3 as flux.Single crystal X-ray diffraction exhibits that Cd4TbO(BO3)3 crystallizes in the monoclinic space group of Cm with unit cell parameters a=7.982(1) (A), b=15.806(3) (A), c=3.487(7) (A), 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)3 crystal in the range of 500-1500 nm is greater than 70%.The content of Tb is 4.624×1021/cm3 per unit volume of crystal 0.3 times of the content of Tb per unit volume of TGG crystal, suggesting that Cd4TbO(BO3)3 is a fairly promising mulit-functional crystal.