在几种压缩速率和其结动力学下,转化为稳定水的水变成冰VII
Charles M Pépin1,2, Ramesh André3,4, Florent Occelli3,4
1CEA, DAM, DIF, F-91297, Arpajon, France. charles.pepin@cea.fr.
Nature communications
|September 19, 2024
概括
研究人员动态压缩水,观察其结成冰VII使用时间解析的X射线衍射. 这项研究澄清了快速压缩下转态水的固化压力,解决了以前的实验矛盾.
科学领域:
- 高压物理学的高压物理
- 材料科学是一种材料科学.
- 物理化学 物理化学
背景情况:
- 水在极大压力下的行为是复杂的,其转变途径不确定.
- 之前的研究对动态压缩过程中水的相变产生了相互矛盾的结果.
研究的目的:
- 为了研究水的动态压缩及其结行为.
- 为了确定一系列压缩速率的元稳态水的固化压力.
- 解决以前关于水的高压相的实验发现中的差异.
主要方法:
- 使用一个动态-piezo-Diamond-Anvil-Cell进行准热压缩.
- 采用时间解析的X射线衍射来监测结构变化.
- 研究的压缩速率从0.1ms到100ms.
主要成果:
- 观察过度压缩水的动态结成冰 VII.
- 在古典核化理论中建立了固化压力和压缩速率之间的关系.
- 在特定条件下 (1.62.0 GPa) 记录了结构演变为冰VI和冰VII的混合物.
结论:
- 这项研究阐明了动态压缩过大的水到冰VII的结路径.
- 提供了对快速压缩下水固化的全面了解.
- 观察到的阶段进化调和了先前研究中的相互矛盾的数据.
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