关于 Yb14MnSb11 的铁磁状态的 XMCD 描述
Aaron P Holm1, Susan M Kauzlarich, Simon A Morton
1Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, USA.
Journal of the American Chemical Society
|August 15, 2002
概括
X射线磁圆二元化显示, (Mn) 在Yb14MnSb11中具有5微B的时刻. 这被周围的反 (Sb) 上相反的时刻部分取消,解释了散装磁化.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 磁力学 磁力学 是一种
背景情况:
- Yb14MnSb11是一种金属间化合物,其结构与Ca14AlSb11相同.
- 离子在离散的AlSb4(9-) 四面体阴离子单位中占据位.
- 了解这些化合物的磁性特性对于潜在的应用至关重要.
研究的目的:
- 通过实验确定 Yb14MnSb11.11 中的的磁矩.
- 为了研究与周围的反之间的磁相互作用.
- 为了使批量磁化测量与局部磁矩相协调.
主要方法:
- 在Mn L23,Sb M45和Yb N45边缘进行X射线磁圆二极化 (XMCD) 光谱.
- 大量磁化测量. 大量磁化测量.
- 对磁离子的理论模型进行比较.
主要成果:
- XMCD证实了Mn离子上的局部磁矩大约为5microB.
- 在Sb M45边缘的弱XMCD信号表明Sb4子上有一个相反的磁矩.
- Yb N45边缘没有显示磁二极化,这表明Yb上没有显著的局部时刻.
- 的光谱与Mn2+配置的理论模型保持一致.
- 大量磁化是由5微B (Mn2+) 的Mn时刻解释的,其中部分取消来自Sb.
结论:
- Yb14MnSb11的磁性属性是由具有高旋转d4配置 (Mn2+) 的Mn离子主导的.
- 在Mn离子和周围的Sb4之间存在显著的磁相互作用,导致部分时刻取消.
- XMCD是一种强大的技术,用于探测局部磁矩及其在复杂材料中的相互作用.
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