Title: Solvation in ionic liquid-water mixtures: A computational study
Journal: Journal of Molecular Liquids
Volume: 292
Pages: 111273
NaFoMat Authors: Luis Miguel Varela Cabo, Luis Javier Gallego, José Manuel Otero Mato, Hadrián Montes Campos
Full Athorship: Jose M Otero-Mato, Volker Lesch, Hadrian Montes-Campos, Jens Smiatek, Diddo Diddens, Oscar Cabeza, Luis J Gallego, Luis M Varela
Year: 2021

Solvation in mixtures of 1-ethyl-3-methylimidazolium acetate ionic liquid with water in a molar concentration of 5% is studied by means of atomistic molecular dynamics (MD) simulations. We employed a spherical coarse-grained parameterization to describe a model solute and we performed MD simulations with positively charged, negatively charged and neutral model spheres and compare the results with those previously reported in pure ionic liquids. Our study reveals that water does not significantly perturb the structure of the electric double layer neither the orientation of ions in the neighborhood of the solute particle. Although water does not seem to play any significant role in the solvation of neutral solutes, there is an excess of water in the first and second ionic solvation shell of both charged solutes, respectively. We also studied the correlation between the electric field around the negatively charged model solute and the orientation of the dipole moment of water molecules, finding that, although the dynamic properties of water molecules are almost unaltered in the presence of the solutes, and the ionic cage around the central solutes is only slightly affected upon water addition, the mobility of the spheres is drastically enhanced.

Citation: Jose M Otero-Mato et al 2021 J. Mol. Liq. 292 111273