在超冷液体中,固态和液态行为之间的交叉
X R Tian1, D M Zhang2,3, B Zhang1
1School of Physics and Electronic Science, East China Normal University, 200241 Shanghai, China.
The Journal of chemical physics
|November 3, 2025
概括
研究人员通过分析原子对动力学,发现了一种了解超冷液体的新方法. 这揭示了两个不同的液态和交叉温度,解释了玻璃过渡附近的复杂行为.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 超冷液体表现出连续的热力学特性,但在玻璃过渡温度 (Tg) 和点 (Tm) 之间的异常动态行为.
- 这些系统中热力学和动力学的脱是玻璃研究中长期存在的难题.
研究的目的:
- 为了描述超冷液体中的热力学-动力学解.
- 将超冷液态动力学分为不同的状态.
- 提出和验证从液态到玻璃状态的途径.
主要方法:
- 对近邻原子对的相对和质量中心坐标的特征放松时间的比率的分析.
- 各种超冷液体的分子动力学模拟.
主要成果:
- 一个基于原子对放松时间的新度量有效地描述了热力学-动力学脱.
- 超冷液体可以分为固态和液态的动态状态.
- 确定了这些状态之间的交叉温度 (Tx),发生在Tm和Tg之间.
- 模拟证实,超冷却液体遵循的路径涉及这种类似固体/类似液体的动态交叉.
结论:
- 拟议的原子层图片为超冷液体中的宏观动态异常提供了微观解释.
- 已识别的交叉提供了对玻璃过渡和超冷状态的性质的新视角.
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