水晶核动力学和机制:相互作用潜力的影响
Porhouy Minh1, Steven W Hall2, Ryan S DeFever3
1Department of Chemistry and Chemical Theory Center, University of Minnesota, Minneapolis, Minnesota 55455, United States.
The journal of physical chemistry. B
|September 4, 2025
概括
在体系统中改变分子间力量会改变晶体结构而不会影响核化速率. 这允许通过受控的多态选择来定制材料特性.
科学领域:
- 材料科学
- 物理化学
- 计算化学
背景情况:
- 控制液体到固体的转变和晶体结构对于定制材料特性至关重要.
- 在体系统中了解分子间相互作用和结晶行为之间的联系仍然是一个挑战.
研究的目的:
- 研究分子间相互作用的变化如何影响体系统中的核化路径和晶体结构.
- 与标准的12-6电位相比,更软的莱纳德-斯电位 (7-6) 对结晶的影响.
主要方法:
- 使用修改的莱纳德-斯电位 (12-6和7-6) 的体系统模拟.
- 在相同的热力学条件下 (超冷和压力) 进行直接比较.
- 核化速率,路径和由此产生的晶体结构 (FCC,BCC) 的分析.
主要成果:
- 在相同的超冷却和压力下,对12-6和7-6电位的核化速率是可比的.
- 12-6潜力主要导致面中心立方体 (FCC) 结构.
- 软化潜力 (7-6) 导致了不同的核化路径,有利于体中心立方体 (BCC) 和FCC结构.
结论:
- 多态选择可以通过修改分子间相互作用而实现,而不会改变核化动力学.
- 这一发现对设计控制晶体多态和自组合过程的策略具有重要意义.
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