揭示面部依赖的冰的生长动力学:从基底和镜表面的分子动力学的洞察
Jihong Shi1, Maxwell Fulford1, Matteo Salvalaglio2
1Department of Physics, King's College London, Strand, London WC2R 2LS, United Kingdom.
The Journal of chemical physics
|February 4, 2025
概括
分子动力学模拟显示了不同晶体面的温度依赖的冰晶生长率. 观察到基底和镜表面之间的增长速度交叉,与准液体层特性和冰习惯过渡相关.
科学领域:
- 大气科学 大气科学
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 冰核形成和增长是具有大气科学,冷生物学和航空学广泛影响的基本过程.
- 详细了解冰晶生长机制,特别是面部特定动力学,仍然是一个重大的科学挑战.
研究的目的:
- 研究六角冰 (Ih) 的基底和镜表面的冰/半液体层 (QLL) 接口上的冰结晶机制.
- 系统地估计面积特定的冰的增长率,在广泛的温度范围内.
- 阐明冰晶形态与生长动力学之间的温度依赖关系.
主要方法:
- 使用TIP4P/Ice和mW粗粒度模型进行分子动力学 (MD) 模拟.
- 模拟涵盖了广泛的温度谱,以捕捉不同的结晶行为.
- 分析了六角冰 (Ih) 与其准液态层 (QLL) 之间的界面上的冰结晶.
主要成果:
- 在基底和镜1表面表征了温度依赖的结晶机制.
- 观察到与基底表面相比,镜表面的生长速度通常更快.
- 在TIP4P/冰模拟中确定了基底表面和镜表面之间的生长速度的温度依赖交叉,与QLL特性和冰习惯过渡有关.
结论:
- 这项研究解读了冰晶形态和生长率之间的复杂,温度依赖的相互作用.
- 结果将观察到的增长率交叉与准液体层厚度和特性变化相关联.
- 结果提供了关于在低蒸汽压力下从柱状转变为血小板冰的已知过渡的见解.
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