第一个原理分子动力学模拟2D水在纳米裂中的自发结过渡
Jian Jiang1, Yurui Gao2, Weiduo Zhu1
1Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States.
Journal of the American Chemical Society
|May 19, 2021
概括
第一原理模拟显示了二维 (2D) 水在纳米裂中的自发结,形成了新的冰结构. 这些二维水晶冰挑战现有规则, 扩大我们对水的理解.
科学领域:
- 凝聚物质物理
- 材料科学
- 物理化学
背景情况:
- 二维冰,类似于大量的水冰,具有多样化的晶体结构.
- 之前对二维冰结构的预测主要依赖于经典分子动力学 (MD) 模拟.
研究的目的:
- 展示2D液体水在疏水纳米裂中的自发冷转变.
- 通过使用第一原则的MD模拟,研究不同压力和温度条件下的各种二维冰结构的形成.
主要方法:
- 使用第一原理分子动力学 (MD) 模拟来研究疏水纳米裂中的水行为.
- 改变侧面压力和温度以观察2D水的自发结和结构转变.
主要成果:
- 在纳米裂中观察到二维液态水的自发结,形成各种晶体结构.
- 在2.5 GPa和250 K的6.0 Å宽纳米裂中发现了单层冰.
- 在4.0 GPa和300 K的8.0 Å宽纳米裂中发现了一种新型的双层冰.
结论:
- 第一原理模拟提供了通过经典模拟不容易探索的独特相位空间.
- 观察到的二维晶体冰不符合常规的冰规则.
- 这项研究突显了纳米尺度限制下的新冰多态的潜力.
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