基于能斯特-普朗克方程并耦合局部平衡蒙特卡洛模拟的稳态电扩散

Steady-State Electrodiffusion from the Nernst-Planck Equation Coupled to Local Equilibrium Monte Carlo Simulations.

作者信息

Boda Dezső, Gillespie Dirk

机构信息

Department of Physical Chemistry, University of Pannonia, P.O. Box 158, H-8201 Veszprém, Hungary.

Department of Molecular Biophysics and Physiology, Rush University Medical Center, Chicago, Illinois 60612, United States.

出版信息

J Chem Theory Comput. 2012 Mar 13;8(3):824-9. doi: 10.1021/ct2007988. Epub 2012 Feb 10.

DOI:10.1021/ct2007988

PMID:26593344

Abstract

We propose a procedure to compute the steady-state transport of charged particles based on the Nernst-Planck (NP) equation of electrodiffusion. To close the NP equation and to establish a relation between the concentration and electrochemical potential profiles, we introduce the Local Equilibrium Monte Carlo (LEMC) method. In this method, Grand Canonical Monte Carlo simulations are performed using the electrochemical potential specified for the distinct volume elements. An iteration procedure that self-consistently solves the NP and flux continuity equations with LEMC is shown to converge quickly. This NP+LEMC technique can be used in systems with diffusion of charged or uncharged particles in complex three-dimensional geometries, including systems with low concentrations and small applied voltages that are difficult for other particle simulation techniques.

摘要

我们提出了一种基于电扩散的能斯特 - 普朗克（NP）方程来计算带电粒子稳态输运的方法。为了封闭NP方程并建立浓度与电化学势分布之间的关系，我们引入了局部平衡蒙特卡罗（LEMC）方法。在该方法中，使用为不同体积元指定的电化学势进行巨正则蒙特卡罗模拟。结果表明，一种通过LEMC自洽求解NP方程和通量连续性方程的迭代过程能够快速收敛。这种NP + LEMC技术可用于复杂三维几何结构中带电或不带电粒子扩散的系统，包括其他粒子模拟技术难以处理的低浓度和小外加电压系统。