了解粗粒度模型中的动态. 第四章 没有了 细粒度和粗粒度动态与斯托克斯-爱因斯坦和斯托克斯-爱因斯坦-德拜关系的联系
Jaehyeok Jin1,2, Gregory A Voth1
1Department of Chemistry, Chicago Center for Theoretical Chemistry, Institute for Biophysical Dynamics, and James Franck Institute, The University of Chicago, Chicago, Illinois 60637, USA.
The Journal of chemical physics
|July 16, 2024
概括
缺少旋转运动的人工加速粗粒度 (CG) 液体动力学. 这项研究通过在水力动力水平上合转换和旋转运动来恢复细粒度 (FG) 扩散,揭示了CG扩散取决于分子形状.
科学领域:
- 计算物理和化学 计算物理和化学
- 软物质物理学 软物质物理学
- 分子动力学模拟的模拟.
背景情况:
- 粗粒度 (CG) 建模简化了复杂的分子系统,但可以引入动态不准确性.
- 在CG模型中缺少旋转运动导致人为加速的动力学.
- 了解细粒度 (FG) 和CG模拟之间的动态可表示性至关重要.
研究的目的:
- 在液体的CG模拟中确定加速动态的原因.
- 开发一种方法,从CG描述中恢复准确的FG扩散.
- 建立CG动力学与已建立的水力动力学理论之间的理论联系.
主要方法:
- 过度缩形式主义应用于CG动态学.
- 使用斯托克斯-爱因斯坦和斯托克斯-爱因斯坦-德比关系与转化放松时间作为代理.
- 将FG转换和旋转运动与水力动力学特性联系起来.
- 使用经典扰动理论和过量的缩缩量,估计分子性质.
主要成果:
- 缺失的旋转运动被确定为加速CG动态的来源.
- 斯托克斯-爱因斯坦和斯托克斯-爱因斯坦-德拜关系被证明是使用转化信息的环境条件.
- 有效的硬球半径接近水力动力半径.
- 过多的,粘度和分子形状之间的关系得到了推导.
结论:
- 当考虑旋转运动时,CG扩散受分子形状的影响.
- 合转移和旋转运动提供了一种从CG模型中恢复FG扩散的方法.
- 这些发现提供了一种替代方法来提高CG模拟的准确性.
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