在高压下,负线性可压缩性和层间隙关闭在分层稀土氧化物 (YCl ((OH) 2) 中
Mengzeng Wu1,2, Jingui Xu1, Dongzhou Zhang3
1Key Laboratory of High-Temperature and High-Pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, Guizhou, China.
Inorganic chemistry
|January 24, 2024
概括
这项研究表明,化氧化 (YCl(OH) 2) 在高压下表现出独特的结构变化,包括由于结合而在b轴上呈负线性压缩性. 这提供了对在极端条件下的多层材料行为的洞察.
科学领域:
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
- 高压物理 高压物理
背景情况:
- 分层材料具有独特的特性,使它们对新的功能性材料至关重要.
- 了解高压下的结构演变对于材料开发至关重要.
研究的目的:
- 在高压下研究YCl(OH) 2的结构演变.
- 为了确定YCl(OH) 的状态方程 (EoS) 参数2.
- 为了阐明观察到异常压缩性背后的机制.
主要方法:
- 同步晶单晶X射线衍射使用钻石细胞高达9.4GPa.
- 高压拉曼光谱学高达10.3GPa.
- 将压力-体积数据与第三阶伯奇-穆尔纳根状态方程相匹配.
主要成果:
- 在实验压力范围内,YCl(OH) 2 保持了对称性.
- 衍生出来的EoS参数:V0 = 142.47 Å3,K0 = 38.2 GPa,K0' = 9.8.8. 这两个参数是:V0 = 142.47 Å3,K0 = 38.2 GPa,K0' = 9.8.
- 沿a,b和c轴观察到明显的压缩行为,沿b轴 (0.4-5.3GPa) 观察到负的线性压缩能力.
结论:
- 异常的b轴压缩归因于O-H··O结合链.
- 由于层间间距的缩小,Y3+协调数从8增加到9.
- 压缩导致层间隙关闭,影响材料的结构反应.
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