Crystal Structure and Magnetism of Ternary CompoundsRE6MSb15,RE= La, Ce andM= Mn, Cu, Zn
Crystal Structure and Magnetism of Ternary CompoundsRE6MSb15,RE= La, Ce andM= Mn, Cu, Zn
复制标题
三元化合物RE6MSb15,RE= La, Ce andM= Mn, Cu, Zn的晶体结构和磁性
DOI：
--
复制
发表时间：
1996
期刊：
影响因子：
--
通讯作者：
P. Woll
中科院分区：
文献类型：
--
作者：
O. Sologub;M. Vybornov;P. Rogl;K. Hiebl;G. Cordier;P. Woll
摘要 一系列新型三元化合物RE6MSb15已通过（a）通过电弧熔炼单质金属锭（M = Mn或Cu）或（b）通过反应烧结冷压粉末混合物（M = Zn）合成。根据单晶 X 射线计数器数据（La6MnSb15 型，Imm2，Z= 2，a= 1.5376，b= 1.9611，c= 0.4314 nm，RF= 0.067，923 次反射 (|F0| > 3σ)）解出了 La6MnSb15 的晶体结构。 Rietveld 使用来自 D5000 西门子衍射仪的 CuKα-X 射线数据对 Ce6MnSb15 的晶体结构进行了精修，确认了原子顺序和晶体对称性 Imm2（RI= 0.049，RF= 0.031），并揭示了 Mn 位点以及其中一个 Sb 位点的小缺陷。采用X射线粉末Guinier技术发现新化合物均与La6MnSb15型具有同构结构。在液氦温度下进行的磁性测量证明，Ce6MnSb15 和 Gd6ZnSb15 两种化合物分别在 7 K 和 15 K 时经历反铁磁转变。 Ce6ZnSb15和Pr6ZnSb15在研究的温度范围内保持顺磁性，而Sm6ZnSb15是Van-Vleck型顺磁体。
Abstract A series of novel ternary compoundsRE6MSb15has been synthesized (a) via arc melting elemental metal ingots (M= Mn or Cu) or (b) via reaction sintering cold compacted powder blends (M= Zn). The crystal structure was solved for La6MnSb15from single crystal X-ray counter data (La6MnSb15-type,Imm2,Z= 2,a= 1.5376,b= 1.9611,c= 0.4314 nm,RF= 0.067 for 923 reflections (|F0| > 3σ)). The Rietveld refinement of the crystal structure of Ce6MnSb15using CuKα-X-ray data from a D5000 Siemens diffractometer confirmed atom order and crystal symmetryImm2 (RI= 0.049,RF= 0.031) and revealed small deficiencies in the Mn site as well as for one of the Sb sites. Employing X-ray powder Guinier techniques the new compounds were all found to be isostructural with the La6MnSb15type. Magnetic measurements performed down to liquid helium temperature give evidence that both compounds Ce6MnSb15and Gd6ZnSb15undergo an antiferromagnetic transition at 7 and 15 K, respectively. Ce6ZnSb15and Pr6ZnSb15remain paramagnetic in the temperature range investigated, whereas Sm6ZnSb15is a Van-Vleck-type paramagnet.