显著的稀土金属氧化物具有平面Si6环
Limin Wang1, Zhongjia Tang, Bernd Lorenz
1Department of Chemistry and the Texas Center for Superconductivity, University of Houston, Houston, Texas 77204-5003, USA.
Journal of the American Chemical Society
|August 6, 2008
概括
新的稀土氧化物La10Si8O3和Ce10Si8O3进行了合成. 这些材料具有独特的3D框架与Si6环,并表现出金属性质,Ce10Si8O3显示反铁磁排序.
科学领域:
- 固态化学 固态化学
- 材料科学是一种材料科学.
- 无机化学 无机化学 无机化学
背景情况:
- 稀土元素在先进材料中至关重要.
- 氧化氧化物具有独特的结构和电子特性.
- 了解新的晶体结构可以为材料设计提供信息.
研究的目的:
- 合成和描述新的稀土氧化物.
- 研究La10Si8O3和Ce10Si8O3.3的晶体结构和结合.
- 探索这些新型化合物的电子和磁性特性.
主要方法:
- 在受控氧气大气下进行高温合成.
- 单晶X射线衍射用于结构确定.
- 带结构计算和磁感应度测量.
主要成果:
- 成功合成了具有新型晶体结构的La10Si8O3和Ce10Si8O3 (空间组P6/mmm).
- 该结构具有3D框架,由共享角的八面体和平面Si6环组成.
- 带结构计算证实了金属行为和优化的La-Si键,具有[Si6]6-离子.
- 拉10Si8O3显示温度独立的偏磁性;Ce10Si8O3显示库里-斯偏磁性和反铁磁性排序在7K以下.
结论:
- 建立了两种新的稀土氧化的合成和结构特征.
- 揭示了一个独特的晶体结构,对稀土材料有意义.
- 展示了独特的磁性行为,突出了稀土元素对电子属性的影响.
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