在超冷的液态水中早期预测螺旋状放松事件
Nico Di Fonte1, Chiara Faccio2,3, Laura Zanetti-Polzi4
1Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio (Coppito 1), L'Aquila 67010, Italy.
The Journal of chemical physics
|July 16, 2024
概括
研究人员模拟了低密度液体 (LDL) 和高密度液体 (HDL) 水之间的过渡. 该研究发现,域形成和分子连接性预测了这种相位过渡,为水提供了洞察力.
科学领域:
- 物理化学 物理化学
- 计算物理 计算物理
- 材料科学 材料科学 材料科学
背景情况:
- 超冷水表现出两个液态:高密度液体 (HDL) 和低密度液体 (LDL).
- 计算研究表明HDL和LDL之间的相位过渡,但实验证据受到快速结晶的阻碍.
- 研究水的液态-液态相转换机制严重依赖于计算模拟.
研究的目的:
- 在TIP4P/2005水模型中模拟和结构性地描述温度诱导的从LDL到HDL类状态的过渡.
- 使用节点总通讯能力 (NTC) 作为一个顺序参数来分析系统放松和相区别.
- 探索过渡机制,并确定域形成的早期预测因素.
主要方法:
- 在TIP4P/2005水模型中模拟出平衡温度引起的过渡.
- 使用节点总传播能力 (NTC) 度量来结构性地描述液体水放松.
- 在LDL阶段分析HDL类域的形成,波动,粗化和稳定.
主要成果:
- 从LDL到HDL类状态的放松过程与类似于旋转的情况一致.
- 在LDL阶段观察到HDL类域的形成和生长.
- 早期形成高度连接的HDL样分子补丁 (高NTC) 与稳定的域发展相关.
结论:
- 该NTC顺序参数有效地区分HDL和LDL水相.
- 该研究提供了对LDL到HDL类过渡的结构性见解,支持一种类似于旋转的机制.
- 在水中,NTC 作为液态-液态相过渡的启动地点的早期预测器.
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