Phase formation and ground state properties of CeCo9Si4
Phase formation and ground state properties of CeCo9Si4
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CeCo9Si4 的相形成和基态性质
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
H. Michor
中科院分区：
文献类型：
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作者：
M. Giovannini;M. Hadwig;R. Pasero;E. Bauer;G. Hilscher;M. Reißner;P. Rogl;H. Michor
通过扫描电子显微镜、电子探针分析和X射线衍射研究了CeCo9+δSi4-δ体系的相关系。基本上单相样品 CeCo9 + δSi4 − δ（具有空间群 I4/mcm 的结构类型 LaFe9Si4）在狭窄的成分范围内形成 - 0.3 ≤ δ < 0.1，其中化学计量的 CeCo9Si4 在空间群 I4/mcm 中表现出完整的结构顺序。通过直流磁化率、磁化强度、比热和电阻率测量研究了固溶体 CeCo9 + δSi4 - δ 中相关 3d 和 4f 电子基态的演化。化学计量的 CeCo9Si4 表现出顺磁性近藤晶格行为，与近铁磁性的 LaCo9Si4 相比，Co 3d 对磁化率的贡献大大降低。尽管如此，与固溶体 LaCo9 + δSi4 - δ 非常相似，当 δ > 0 时，在 CeCo9 + δSi4 - δ 中观察到弱铁磁性，这归因于 Si 亚晶格的替代无序。
The phase relations of the CeCo9 + δSi4 − δ system have been studied by means of scanning electron microscopy, electron microprobe analysis and x-ray diffraction. Essentially single phase samples CeCo9 + δSi4 − δ (structure-type LaFe9Si4 with space group I4/mcm) are formed in a narrow composition range − 0.3 ≤ δ < 0.1, where stoichiometric CeCo9Si4 exhibits full structural order in space group I4/mcm. The evolution of the ground state of correlated 3d and 4f electrons in the solid solution CeCo9 + δSi4 − δ has been investigated by dc susceptibility, magnetization, specific heat and resistivity measurements. Stoichiometric CeCo9Si4 exhibits paramagnetic Kondo lattice behaviour with a largely reduced Co 3d contribution to the magnetic susceptibility as compared to nearly ferromagnetic LaCo9Si4. Nonetheless, very similar to the solid solution LaCo9 + δSi4 − δ, weak ferromagnetism is observed in CeCo9 + δSi4 − δ for δ > 0 and is attributed to substitutional disorder at the Si-sublattice.