First Principles Molecular Dynamics Simulations of Deep Eutectic Solvent Systems

Given the complexities of (room-temperature) ionic liquids and deep eutectectic solvents, describing their interactions via Kohn-Sham density functional theory (KS-DFT) offers an attractive alternative to the use of molecular mechanics force fields.  However, first principles simulations are computationally much more demanding and, hence, are limited to relatively small system sizes and short molecular dynamics or Monte Carlo trajectories.  In this work, first principles molecular dynamics simulations are utilized to compare the structures and (short-time) dynamics of two solvents systems containing the chloride anion: the ionic liquid 1-butyl-3-methylimidazolium chloride and the deep eutectic solvent consisting of urea and choline chloride.  For both solvent systems, the influence of hydration and the solvation of metal cations are investigated.