Ce_5AgBi_3的合成、结构与磁性性能

Synthesis,Structure and Property of New Intermetallic Compound:Ce_5AgBi_3

用电弧炉熔炼法制备了新的三元金属间化合物Ce_5AgBi_3,用Rietveld方法对其结构进行了精修,该化合物为Hf_5CuSn_3结构(空间群p63/mcm),其中Ce、Ag和Bi分别占据Hf、Cu和Sn的位置,晶胞参数为:a=b=9.7163(3)(?),c=6.6228(2)(?),V=541.47(5)(?)~3.该结构特点是沿着c轴方向的层状结构.其中6g的Ce和Bi组成六边形网状平面结构,2d的Ag和4f位置的Ce分别占据由Ce-Bi六边形所形成的沿着c轴方向的两种隧道中.用PPMS对Ce_5AgBi_3的磁性和比热性能做了分析.该化合物低温下为反铁磁性,奈尔温度为3.8K,高温时符合居里-外斯定律,有效磁量子数为2.67μB,表明其磁矩都是由Ce^(3+)提供.

The title new compound Ce5AgBi3 was synthesized by arc melting method followed by annealing. The crystal structure refined using Rietveld method and X-ray powder diffraction data shows that it is similar to Hf5CuSn3 with space group p63/mcm （No.193）. The unit cell parameters are a = b=9.7163（3）A, c=6.6228（2）A and V=541.47（5）A^3. The structure is characterized by layers of Ce-Bi net formed by Ce and Bi at 6g position. Ce at 4f position and Ag at 2d position are separated in those two different kinds of Ce-Bi hexagon tunnels along c axes, respectively. Magnetism and specific heat property of Ce5AgBi3 are measured using PPMS. Ce5AgBi3 is antiferromagnetism and complies with Curie-Weiss law above TN=3.8K. The calculated moment is 2.67μm fitted well with μeff of Ce^3＋, which means that the magnetism of Ce5AgBi3 is mainly offered by Ce^3＋.