arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2301.05019physics.chem-ph
收藏

用隐式溶剂模型计算静电力的精确边界积分公式

Accurate boundary-integral formulations for the calculation of electrostatic forces with an implicit-solvent model

Ian Addison-Smith, Horacio V. Guzmán, Christopher D. Cooper

摘要:

用泊松-玻尔兹曼方程精确计算力是具有挑战性的,因为它需要分子表面上的电场。在这里,我们提出了一个计算的电场的溶质-溶剂界面上,是准确的分段线性变化的潜力和分析四种不同的替代品,使用边界元法计算力。我们对两种情况进行了验证:孤立分子和两个相互作用的分子。我们的研究结果表明,边界元法优于有限差分法,因为后者需要一个更精细的网格比在溶剂化能量计算得到可接受的精度的力量,而相同的表面网格比标准的能量计算是适当的边界元法。在四种评估的力计算方法中,我们看到最准确的一种是基于麦克斯韦应力张量。然而,对于一个实际的应用,如barnase-barstar复杂,基于能量泛函的变化,这是不太准确的方法,给出了等效的结果。这种分析对于在高精度是关键的应用中使用泊松-玻尔兹曼方程进行力计算是有用的,例如,用于馈送分子动力学模型或使得能够研究大分子结构之间的相互作用,如吸附在基底上的病毒。

英文摘要:

An accurate force calculation with the Poisson-Boltzmann equation is challenging, as it requires the electric field on the molecular surface. Here, we present a calculation of the electric field on the solute-solvent interface that is exact for piece-wise linear variations of the potential and analyze four different alternatives to compute the force using a boundary element method. We performed a verification exercise for two cases: the isolated and two interacting molecules. Our results suggest that the boundary element method outperforms the finite difference method, as the latter needs a much finer mesh than in solvation energy calculations to get acceptable accuracy in the force, whereas the same surface mesh than a standard energy calculation is appropriate for the boundary element method. Among the four evaluated alternatives of force calculation, we saw that the most accurate one is based on the Maxwell stress tensor. However, for a realistic application, like the barnase-barstar complex, the approach based on variations of the energy functional, which is less accurate, gives equivalent results. This analysis is useful towards using the Poisson-Boltzmann equation for force calculations in applications where high accuracy is key, for example, to feed molecular dynamics models or to enable the study of the interaction between large molecular structures, like viruses adsorbed onto substrates.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑