在非结合修改的WAC模型中,结晶和液体-液体临界点
Erik Lascaris1, Francesca Marchese1, Nicole Gaspar1
1Department of Chemistry & Physical Sciences, Pace University, New York, New York 10038, USA.
The Journal of chemical physics
|July 22, 2024
概括
分子动力学模拟显示,具有液体-液体临界点 (LLCP) 的液体形成多个晶体相. 缺乏LLCP的模型往往会形成眼镜,可能会阻碍LLCP的发生.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 计算物理 计算物理
背景情况:
- 液体-液体临界点 (LLCP) 在单元液体中已知,但它们形成的条件尚未完全理解.
- 液体的晶化行为与LLCP之间的关系需要进一步研究.
研究的目的:
- 研究液体中LLCP和晶相之间的相互作用.
- 确定具有和没有LLCPs的模型之间的结晶行为中的关键差异.
主要方法:
- 使用修改WAC (mWAC) 模型进行分子动力学模拟.
- 将显示LLCP的mWAC模型与不显示LLCP的mWAC模型进行比较.
主要成果:
- 具有LLCP的模型表现出多个稳定的晶体相,包括一个类似冰的超离子固态离子导体.
- 没有LLCP的模型显示,在更广泛的温度范围内,形成玻璃的倾向更大.
- 在某些模型中形成玻璃可能会防止LLCPs的发生.
结论:
- 一个LLCP的存在与多个结晶相的形成相关.
- 玻璃形成可能会抑制LLCP的发生.
- 需要进一步的研究来确定这些发现的一般适用性.
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