新型钨青铜型晶体Ca_(0.28)Ba_(0.72)Nb_2O_6的生长研究

Single Crystal Growth of a New Tetragonal Tungsten Bronze Ca_(0.28)Ba_(0.72)Mb_2O_6 Crystal

研究了Ca0.28Ba0.72Nb2O6(CBN-28)多晶料的制备和单晶的生长,用提拉法成功生长出CBN-28单晶。从X射线粉末衍射数据计算了CBN-28晶体的晶胞参数,并对其粉末衍射图各衍射峰进行了指标化。CBN晶体属四方晶系4mm点群。晶胞参数为a=1.2432(±2)nm,c=0.3957(±1)nm。采用浮力法测得其平均密度为5.372g／cm3,测得其莫式硬度为7,并通过测量CBN-28的介电性质,确定其居里点为260℃。

Polycrystalline material was prepared by the solid reaction, and the single crystal of Ca0.28Ba0.72Nb2O6 (CBN-28) was successfully grown by Czochralski method. The average density of CBN-28 is determined to be 5.372 g/cm3 by the Buoyancy method, and the Moh's hardness is 7. The crystal parameters of CBN-28 crystal were calculated from XRD data, it belongs to tetragonal 4 mm point group with a = 1.2432(±2) nm and c = 0.3957(±1) nm. The diffraction peaks in the X-ray powder diffraction pattern were indexed. The curie temperature of grown crystal was measured to be 260°C resulting from dielectric constant measurement.