Multi-scale Modeling of Structure, Dynamic and Thermodynamic Properties of Imidazolium-based Ionic Liquids: Ab initio DFT Calculations, Molecular Simulation and Equation of State Predictions

Abstract

Ionic liquids have received considerable attention by the chemical industry in recent years, mostly towards the development of environmentally benign processes. In this work, microscopic structure, dynamic and thermodynamic properties of imidazolium-based ionic liquids are calculated using theoretical models that cover a wide range of length and time scales, from ab initio density functional theory (DFT) calculations to atomistic molecular simulation and finally to a macroscopic equation of state based on perturbation theory. Different ionic liquids and polar solvents are examined and calculations are performed over a wide range of conditions. Model calculations are compared against literature experimental data. In all cases, the agreement between experiment and calculations/theory is very good. Thus, it is verified that carefully selected models can be used for reliable estimation of properties, even in the absence of experimental measurements.