重新审视Ce-Ni-Si系统:更多同类化合物?
Fainan Failamani1,2, Andriy Grytsiv1, Jiri Bursik3
1Institute of Materials Chemistry, University of Vienna, Währingerstraße 42, Vienna A-1090, Austria.
Inorganic chemistry
|May 2, 2024
概括
这项研究重新研究了Ce-Ni-Si系统,确定了两种新型六角化合物和一种新的单临结构类型,Ce3Ni4Si2. 这些发现扩展了已知的Ce-Ni-Si三元系统,并在RE-Ni-Si系统中引入了一个新的同类序列.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 该Ce-Ni-Si三元系统对其多样化的金属间化合物有兴趣.
- 之前的研究已经确定了各种各样的阶段,但丰富的地区需要进一步调查.
研究的目的:
- 综合重新调查Ce-Ni-Si系统的富含的地区.
- 在这个系统中识别和描述新型化合物和结构类型.
主要方法:
- 使用X射线单晶,粉末和电子衍射技术.
- 使用电子微探测器和热分析进行表征.
- 进行了瑞特维尔德精细化和单晶X射线衍射以确定结构.
主要成果:
- 确定了两个新的六边形化合物: τ-Ce20+Ni36+Si30-和 τ'-Ce30+Ni50+Si42-.
- 确定了 τ-Ce20+Ni36+Si30- (Sm10Ni20.8P15类型) 和 τ'-Ce30+Ni50+Si42- (Tb15Ni28P21类型) 的晶体结构.
- 发现了Ce3Ni4Si2的新型单临床结构类型,属于RE(3×2Ni(3×2Si(2在RE-Ni-Si系统中的新同源系列.
结论:
- 重新调查成功地扩大了Ce-Ni-Si相位图的知识,特别是在富含的地区.
- 发现新型化合物和新的同源序列为RE-Ni-Si材料的结构性质关系提供了洞察力.
- 结构特征揭示了独特的特征,如角落共享的Si多面体块和状的链.
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