平衡2D和3D硬球晶体的洞统计
Haina Wang1, David A Huse2, Salvatore Torquato3
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
The Journal of chemical physics
|August 15, 2024
概括
我们开发了一种新的方法来研究硬球晶体中的大孔. 这揭示了晶体洞统计中的振荡模式,与流体中看到的平稳增长不同.
科学领域:
- 统计力学 统计力学
- 凝聚物质物理学 凝聚物质物理学
- 计算化学计算化学
背景情况:
- 了解多体系统的结构依赖于分析发现各种大小的球形孔的概率.
- 空无条件近邻概率函数 (GV(r)) 对硬球流体的研究很好,但对硬球晶体的理解很差,特别是对于大型洞.
- 在晶体相中,大孔是罕见的,这给传统方法带来了计算挑战.
研究的目的:
- 开发和应用一种新的偏向采样方案,准确计算平衡硬球的洞统计数据.
- 扩大洞半径 (r) 的可访问范围远远超出以前的限制,特别是对于晶相.
- 在硬球系统中调查洞统计,局部顺序和协调几何之间的关系.
主要方法:
- 引入了一个偏向采样方案,以克服模拟罕见的大孔的计算挑战.
- 准确确定无空条件近邻概率函数 (GV(r)) 对于流体,六合体和晶体状态的硬球.
- 计算Delaunay细胞的局部包装分数分布 (f ((φl)).
主要成果:
- 在晶体和六度状态下,GV (r) 呈现出振荡幅度的振荡,随着包装分数的快速增加,与流体状态中的单调增加形成鲜明对比.
- 2D晶体GV的振荡 (r) 与洞附近的局部方向顺序有很强的相关性.
- 3D GV(r) 的变化表明四面体和八面体孔几何之间的过渡,验证GV(r) 作为协调探针.
- 局部包装分数分布 f ((φl) 交换机的过量库尔托斯在维度 d ≤ 3 的过渡性全球包装分数上发出信号.
结论:
- 开发的偏向采样方法提供了前所未有的访问中等长度尺度的硬球晶体中洞统计数据.
- GV(r) 是一种强大的工具,用于描述水晶阶段的局部结构和协调.
- 这些发现对理解分子尺度上的溶解和疏水性有意义.
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