Significant Cation Effects in Carbon DioxideIonic Liquid Systems

Carbon dioxideionic liquid systems are of great current interest, and significant efforts have been made lately to understand the intermolecular interactions in these systems. In general, all the experimental and theoretical studies have concluded so far that the main solutesolvent interaction takes effect through the anion, and the cation has no, or only a secondary role in solvation. In this theoretical approach it is shown that this view is unfounded, and evidence is provided that, similarly to the benzeneCO2 system, dispersion interactions are present between the solute and the cation. Therefore, this defines a novel site for tailoring solvents to tune CO2 solubility.