重述了NdGa及其化物相的化行为
Vitalii Shtender1, Johan Cedervall1, Gustav Ek1
1Department of Chemistry - Ångström Laboratory, Uppsala University, Box 538, Uppsala 751 21, Sweden.
新 (NdGa) 化物和化物相被合成并进行结构性特征. 该研究揭示了NdGa化物中明显的结构阶段和排序,在较高度下形成三重超结构.
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:
- 新 (NdGa) 是一种金属间化合物,在储存中具有潜在的应用.
- 了解NdGa化物的结构性行为对于优化吸收特性至关重要.
- 之前对类似的金属间化物进行的研究表明,在吸收时会发生复杂的结构变化.
研究的目的:
- 合成和表征新 (NdGa) 化物和化物相.
- 为了阐明这些阶段的晶体结构和的排序.
- 为了研究 NdGa 在不同压力下的相位过渡和吸收极限.
主要方法:
- 从高质量的 NdGa 样本中合成 NdGa 水化物和乳化物相.
- 使用粉末和单晶X射线衍射进行结构性表征.
- 用中子粉衍射来确定原子的位置和排序.
主要成果:
- NdGa可以吸收高达 NdGaH(D) 1.1 的气,并保留了方形CrB类型的结构.
- 在更高的压力下,NdGaH(D) 1.6形成一个三重的上层结构 (Cmcm LaGaH1.66类型),具有四面体和三角形-双金字塔空隙中的有序原子.
- 对于1.2至1.6之间的H度,三重的上层结构仍然存在,而较低的度则返回到四面体空隙中含有的CrB型结构.
结论:
- NdGa表现出复杂的吸收行为,形成不同的结构阶段.
- 原子占据了特定的间歇点,导致有序的结构和超结构.
- 三重上层结构和单层结构之间的相位边界被确定为大约在x = 1.15.
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