Removing systematic errors in interionic potentials of mean force computed in molecular simulations using reaction-field-based electrostatics
Removing systematic errors in interionic potentials of mean force computed in molecular simulations using reaction-field-based electrostatics
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DOI：
10.1063/1.3081138
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发表时间：
2009-03-14
影响因子：
4.4
通讯作者：
Baumketner, Andrij
中科院分区：
文献类型：
--
作者：
Baumketner, Andrij
反应场法处理静电相互作用的性能在模拟水中溶解的离子中得到了检验。通过伞状取样和分子动力学模拟计算了氯化钠离子对之间以及赖氨酸和天冬氨酸侧链之间的平均作用力势。结果发现，与晶格和计算相比，基于电荷基团的反应场处理方法在离子缔合能方面产生了较大的误差，表现出强烈的系统依赖性。基于原子的反应场的实现被认为(I)改善了平均力势的整体质量，并且(Ii)消除了对模拟框大小的依赖。建议在混合介质的反应场模拟中采用基于原子的截断方法。
The performance of reaction-field methods to treat electrostatic interactions is tested in simulations of ions solvated in water. The potential of mean force between sodium chloride pair of ions and between side chains of lysine and aspartate are computed using umbrella sampling and molecular dynamics simulations. It is found that in comparison with lattice sum calculations, the charge-group-based approaches to reaction-field treatments produce a large error in the association energy of the ions that exhibits strong systematic dependence on the size of the simulation box. The atom-based implementation of the reaction field is seen to (i) improve the overall quality of the potential of mean force and (ii) remove the dependence on the size of the simulation box. It is suggested that the atom-based truncation be used in reaction-field simulations of mixed media.