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Ionic liquids (ILs) refer to a group of low-melting–point salts composed entirely of ions. ILs are generally regarded as “designer solvents” due to the vast number of cation and anion combinations equate up to 1012. Interest in these compounds, which are often reputed as the green, biocompatible solvents of the future, is still increasing rapidly due to their near-zero vapor pressure, chemical and thermal stability, and widely tunable properties as regards viscosity, polarity, and hydrogen bond basicity.