微秒级分子动力学模拟双层冰的相变:受限水中的动力约束
Weiduo Zhu1, Yiyao Li2, Haidi Wang1
1Department of Physics, Hefei University of Technology, Hefei, Anhui 230009, China.
The journal of physical chemistry. B
|June 9, 2025
概括
研究人员在纳米水中发现了一种新的冰相,双层五分六合冰 (BL-PHI). 这一新型阶段在高压下慢慢形成,并表现出独特的结构性质,影响水.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 物理化学 物理化学
背景情况:
- 水在受限下表现出复杂的相位行为.
- 了解纳米封闭水对于各种科学和技术应用至关重要.
- 水变成冰的阶段过渡是一个基本的过程,具有跨学科的影响.
研究的目的:
- 为了研究水的相位行为被限制在两个平行光滑的墙壁之间.
- 探讨在低度条件下水变成冰的过渡阶段.
- 为了描述新观察到的二维 (2D) 双层晶体冰相.
主要方法:
- 经典分子动力学 (MD) 模拟.
- 机器学习潜力 (MLP) MD模拟.
- 在不同压力下分析水变成冰的相变.
主要成果:
- 观察到三种不同的二维双层 (BL) 晶体冰相:BL-ice I,BL-VHDI和一个新的BL-PHI.
- BL-PHI阶段以相互锁定的五角形和六角形环为特征,通过弱的第一阶段过渡形成.
- BL-PHI在中高侧压 (400900 MPa) 时出现,并且由于扩散激活能量较高,其形成过程较慢.
- 所有观察到的双层冰的过渡温度都取决于压力.
结论:
- BL-PHI的发现为纳米封闭水的复杂相位行为提供了新的见解.
- BL-PHI的独特结构和形成动力学突出显示了水相转换对封闭和压力的敏感性.
- 对纳米封闭水相的进一步研究可以推进从地球化学到材料设计的领域.
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