在RE2Ru3Ge5 (RE=Pr,Sm,Dy) 的新多态体中的电荷密度波
Daniel E Bugaris1, Christos D Malliakas1,2, Fei Han1
1Materials Science Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.
Journal of the American Chemical Society
|February 17, 2017
概括
由于电荷密度波 (CDW),新的稀土鲁基曼化物化合物 (RE2Ru3Ge5) 呈现出低温结构转变. 这种过渡涉及到链的扭曲和同时发生的电子状态变化.
科学领域:
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
背景情况:
- 稀土 (RE) 鲁日尔曼化物 (RE2Ru3Ge5) 是已知的金属间化合物.
- 了解它们的结构和电子特性对于材料设计至关重要.
研究的目的:
- 为了合成和描述RE2Ru3Ge5化合物的新多态 (RE = Pr, Sm, Dy).
- 研究归因于电荷密度波 (CDW) 的低温结构转变.
- 阐明结构转换和电子性质之间的关系.
主要方法:
- 单晶生长使用流量方法.
- 用X射线衍射 (XRD) 来确定晶体结构 (高温和低温).
- 电荷传输测量 (电阻,霍尔效应,磁阻).
- 磁性测量和热容量分析.
- 射线吸收近边谱学 (XANES) 和电子带结构计算.
主要成果:
- 对于Pr,Sm和Dy类型的Pr,Sm和Dy类型,四角形P4/mnc结构与Sc2Fe3Si5类型得到确认.
- 观察到与电荷密度波 (CDW) 相关的低温结构转变.
- 对于Pr (~200 K) 和Sm (~175 K) 化合物,确定了CDW订单温度 (TCDW).
- 一维齐格扎格Ge链的周期性扭曲是CDW状态的特征.
- 与CDW转换同时检测到同时发生的电子状态转换.
结论:
- 合成的RE2Ru3Ge5化合物代表了一种新的多态体,有可能产生有趣的电子现象.
- 观察到的电荷密度波过渡显著影响材料的性质.
- 结构扭曲和电子状态之间的相互作用提供了对这些germanides的基本物理学的洞察.
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