Influence of the Silicon Composition on the Crystallographic Properties of the New Ferromagnetic Ternary Silicides U2Fe17-ySiy (3.3 ≤ y ≤ 4.5) and U2Co15Si2
Influence of the Silicon Composition on the Crystallographic Properties of the New Ferromagnetic Ternary Silicides U2Fe17-ySiy (3.3 ≤ y ≤ 4.5) and U2Co15Si2
复制标题
硅成分对新型铁磁三元硅化物U2Fe17-ySiy (3.3≤y≤4.5)和U2Co15Si2晶体性能的影响
DOI：
10.1006/jssc.1993.1167
复制
发表时间：
1993
影响因子：
5.4
通讯作者：
J. Etourneau
中科院分区：
文献类型：
--
作者：
T. Berlureau;P. Gravereau;B. Chevalier;J. Etourneau
三元硅化物U_2Fe_(17-y)Si_y经熔炼和淬火后存在3.3≤y≤_(4.5)，但在85 0~900°C热处理后部分分解。由单晶和粉末的X射线衍射仪测定，它们的晶体结构来自六方的Th2Ni_(17)型，但与硅的含量密切相关。当y=3.7时，部分铀位被铁原子对部分取代，反之亦然。这种结构与观察到的二元化合物Ho2Fe17的结构有一些相似之处。另一方面，对于y=4.2时，所有的铀原子和铁原子对都是统计分布的。而三元硅化物U2Co15Si2则为Th2Ni17型结构，经850℃热处理后为单相。在所有化合物中，铁或钴原子对永远不会被硅原子取代。
Abstract After melting and quenching, the ternary silicides U 2 Fe 17- y Si y exist far 3.3 ≤ y ≤ 4.5 but they partially decompose after annealing at 850-900°C. Their crystal structure, determined by X-ray diffractometry on both single crystals and powder, derives from the hexagonal Th 2 Ni 17 -type but depends strongly on the silicon content. For y = 3.7 some uranium sites are partially replaced by pairs of iron atoms and conversely. This structure shows some similarities to that observed for the binary compound Ho 2 Fe 17 . On the other hand, for y = 4.2, all the uranium atoms and pairs of iron atoms are statistically distributed. In contrast, the ternary silicide U 2 Co 15 Si 2 , which is obtained as single phase after annealing at 850°C, adopts the Th 2 Ni 17 -type structure. In all compounds, iron or cobalt atoms of the pair are never substituted by silicon atoms.