在 tert-butanol/水混合物中可转移的局部密度依赖摩擦
Moritz Mathes1, Viktor Klippenstein1, Nico F A van der Vegt1
1Department of Chemistry, Technical University of Darmstadt, 64287 Darmstadt, Germany.
The Journal of chemical physics
|May 10, 2024
概括
粗粒度模型现在可以更好地表示分子混合物. 具有局部密度依赖摩擦的新朗格温方程恒温器可以改善复杂系统的动态可转移性.
科学领域:
- 计算化学和分子动力学
- 材料科学和软物质材料科学和软物质
背景情况:
- 粗粒度 (CG) 模型通过使用有效电位来简化全原子 (AA) 模拟.
- CG模型经常失去摩擦,加速动力学,特别是在隐性溶剂模型中.
- 兰杰文方程 (LE) 恒温器重新引入摩擦以捕捉长时间动态.
研究的目的:
- 提高对异质分子混合物的CG模型的可表示性和可转移性.
- 开发一种新的LE恒温器,其摩擦依赖于局部粒子密度 (LD).
主要方法:
- 一个LE恒温器的参数化,其摩擦系数取决于局部粒子密度 (LD).
- 使用记忆内核代优化 (IOMK) 方法的马科夫变体,代优化恒温器摩擦.
- 在各种组成中模拟三butanol/水混合物,表现出集群行为.
主要成果:
- 开发的依赖LD的摩擦恒温器准确地复制了AA的扩散系数.
- 该模型在全系列混合物组合中显示出出色的可转移性.
- 该方法有效地解决了异质分子系统的动态.
结论:
- 在LE恒温器中,局部密度依赖的摩擦显著改善了CG模型的动态性.
- 这种方法提高了复杂混合物的CG模型的可转移性.
- 这些发现为模拟分子系统提供了更准确和更通用的方法.
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