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Updated: Jun 13, 2025

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High Pressure Single Crystal Diffraction at PX^2
Published on: January 16, 2017
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高压下的哥伦比亚单晶CoV2O6:一个XRD和拉曼光谱研究
Josu Sánchez-Martín1, Pierre Bouvier2, Gaston Garbarino3
1Departamento de Física Aplicada-ICMUV, Universidad de Valencia, Dr. Moliner 50, Burjassot, Valencia 46100, Spain.
概括
高压诱导了两个相位转换在正方体结石瓦纳酸盐 (CoV2O6). 这些可逆转变涉及结构变化和体积减少,详细通过X射线衍射和拉曼光谱学.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 晶体学 晶体学是指结晶学.
背景情况:
- 正方形柱石CoV2O6是一种具有潜在应用的材料.
- 了解其在极端条件下的行为对于材料科学至关重要.
研究的目的:
- 为了研究高压下奥托罗姆比克科伦比特 CoV2O6的结构和振动特性.
- 为了识别和描述由压力诱导的相位过渡.
主要方法:
- 单晶X射线衍射 (XRD) 达到了54.9GPa.
- 拉曼光谱仪高达54.9 GPa.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 在20.0 GPa和45.6 GPa时观察到两个可逆相变.
- 第一个过渡 (20.0 GPa) 是同结构的,具有4.7%的体积减小和VO6八面体的对称.
- 在45.6 GPa以上确定了一种新的单临床多态 (空间组P21/c).
- 在4.9GPa以下,该材料转化为布兰尼特多态.
结论:
- 高压显著改变了CoV2O6的结构,导致了不同的多态.
- 观察到的转变是可逆的,在释放压力时具有复杂的行为.
- 实验发现与理论DFT计算相一致.
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