在压力下对玻璃水的核量子效应:玻璃化和压力诱导的转变
Ali Eltareb1,2, Bibi A Khan1,2, Gustavo E Lopez2,3
1Department of Physics, Brooklyn College of the City University of New York, Brooklyn, New York 11210, USA.
The Journal of chemical physics
|December 16, 2024
概括
核量子效应显著改变了无形冰和六角冰的密度和键几何. 这些量子效应对于对水的定量理解至关重要.
科学领域:
- 计算化学计算化学
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 了解水的相位行为,包括无形和晶体冰的形式,至关重要.
- 众所周知,核量子效应 (NQE) 影响水等轻分子的特性.
- 经典模拟通常难以捕捉对凝聚物质系统的微妙量子力学影响.
研究的目的:
- 研究核量子效应 (NQE) 对水的玻璃化和压力诱导的相变的影响.
- 为了比较H2O和D2O的经典分子动力学 (MD) 和通路积分MD (PIMD) 模拟.
- 在不同的条件下分析键的结构和几何变化.
主要方法:
- 执行了经典的MD和路径整体MD (PIMD) 模拟.
- 使用了q-TIP4P/F水模型.
- 在广泛的温度和压力范围内模拟同热冷却 (玻璃化) 和同热压缩/解压 (相变).
主要成果:
- NQE显著影响在玻璃化过程中形成的中间无形冰 (IA) 的密度.
- 在LDA,HDA和冰中,NQE会导致较长且较少的线性键.
- NQE稍微降低了LDA/ice Ih到HDA转换的压力,表明一个更软的键网络.
结论:
- 经典模拟捕捉了水和冰的定性行为,但缺乏定量准确性.
- 对于精确描述水的无形和晶体相来说,NQE是必不可少的.
- 键的几何结构对NQE比无形冰的整体结构更敏感.
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