Simulations of room temperature ionic liquids: From polarizable to coarse-grained force fields

TL;DR

This paper reviews classical molecular dynamics simulations of room temperature ionic liquids, focusing on different force fields from all-atom to coarse-grained, highlighting their applications, advantages, and limitations.

Contribution

It provides a comprehensive overview of simulation techniques and force fields used for RTILs, emphasizing the balance between detail and computational efficiency.

Findings

All-atom force fields can include polarization effects.

Coarse-grained models reduce computational cost.

Various force fields have been successfully applied to RTILs.

Abstract

Room temperature ionic liquids (RTILs) are solvent with unusual properties, which are difficult to characterize experimentally because of their intrinsic complexity (large number of atoms, strong Coulomb interactions). Molecular simulations have therefore been essential in our understanding of these systems. Depending on the target property and on the necessity to account for fine details of the molecular structure of the ions, a large range of simulation techniques are available. Here I focus on classical molecular dynamics, in which the level of complexity of the simulation, and therefore the computational cost, mostly depends on the force field. Depending on the representation of the ions, these are either classified as all-atom or coarse-grained. In addition, all-atom force fields may account for polarization effects if necessary. The most widely used methods for RTILs are described together with their main achievements and limitations.