在部分填充的 skutterudites 中异常的双元件填充
Lili Xi1, Jiong Yang, Wenqing Zhang
1State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.
Journal of the American Chemical Society
|March 28, 2009
概括
在 skutterudites 中的双元素填充通常在单元素极限之间具有联合填充分数 (FF). 然而,Na-Eu的共同填充表现出异常的行为,超过个体限制并达到完全填充.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 计算化学计算化学
背景情况:
- 单元填充中的化合物如 skutterudites 具有填充分数极限 (FFL).
- 在 skutterudites 中的双元填写通常会显示单个 FFL 之间的结合 FF.
研究的目的:
- 研究双元填充 skutterudites 的填充分数行为.
- 在 skutterudites 中分析 (Na) 和欧 (Eu) 的异常共同填充行为.
主要方法:
- 一开始的计算来确定填充分数.
- 电子结构分析以了解结合和电荷状态.
主要成果:
- 双元件FF通常随着其他填充剂的增加线性地减少,单元件FFL之间总FF.
- Na-Eu 配填表表现出异常行为,总的 FF 超过单个 Na-only 和 Eu-only FFL.
- 与其他双元组合不同,Na-Eu配填可以接近完全填充.
结论:
- 异常的Na-Eu辅充行为归因于电子结构的修改.
- 充电改变了Na和Eu的状态,增加了电子占用率,并降低了有效电荷状态.
- 这些电子效应影响Na-Eu相互作用,导致观察到的异常填充.
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