A poisson P³M force field scheme for particle-based simulations of ionic liquids

In this work we propose a force-field scheme for the self-consistent particle-based simulation of electrolytic solutions. Within this approach, the electrostatic interactions are modeled with a particle-particle-particle-mesh (P³M) algorithm, where the long-range components of the force are resolved in real space with an iterative multi-grid Poisson solver. Simulations are performed where the solute ions are treated as Brownian particles governed by the full Langevin equation, while the effects of the solvent are accounted for with the implicit solvent model. The main motivation of this work is to efficiently extend the modeling capability of the standard particle-based approaches to liquid systems characterized by a spatially inhomogeneous charge distribution and realistic, non-periodic boundary conditions. Examples of such systems are large polymer chains, biological membranes, and ion channels.