对稀土化物类型氧化物的比较高压研究
Pablo Botella1, David Vie2, Leda Kolarek3
1Departamento de Física Aplicada-ICMUV, MALTA Consolider Team, Universitat de Valencia, Valencia 46100, Spain.
Crystal growth & design
|December 22, 2025
概括
高压研究显示,稀土高氧化物表现出复杂的结构行为,包括晶格扭曲和软化,受配置和阴离子乱的影响.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 高压物理 高压物理
背景情况:
- 具有化物结构的稀土氧化物在先进材料中至关重要.
- 配置极大地影响了高材料的特性.
- 了解在极端压力下材料的行为对于技术应用至关重要.
研究的目的:
- 为了比较研究两个具有不同配置的化物类型稀土氧化物的高压结构反应.
- 阐明在极端压缩下结构稳定性和振动性质变化背后的机制.
- 探索离子乱在这些材料的弹性中的作用.
主要方法:
- 基于同步射线的粉末X射线衍射高达30 GPa.
- 拉曼光谱仪可达20 GPa.
- 分析压缩性,振动模式和结构相变的分析.
主要成果:
- 无论是 (CePr) -O2-δ还是 (CePrLa) -O2-δ都保留了化物结构,其异常 (压缩性平原,振动模式变化) 在9-16 GPa之间,归因于格子扭曲.
- (CePrLa) -O2-δ显示在22GPa以上的无形化,表明稳定性降低.
- 异常后散装模量略有下降表明格子变软;拉曼数据表明F2g模式的抑制与混乱和压力下的部分重新排序.
结论:
- 配置,阴离子大小和压力密切控制稀土高氧化物的结构稳定性和振动性质.
- 局部格子扭曲和结合角度曲,而不是突然的相位过渡,是观察到的异常的特征.
- 该研究提供了对这些材料在极端条件下的弹性和混乱机制的见解.
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