Concentration Dependence of Ion Pairing in Imidazolium‐Based Ionic Liquid Solutions

Abstract

Abstract Infrared vibrational spectroscopy was used to probe concentration‐dependent ion pair dissociation of imidazolium‐based ionic liquids with three different halide anions (I − , Br − , and Cl − ) in deuterated chloroform. Dissociation of the ion pairs at low concentrations of ionic liquids was found to be the easiest for ionic liquid with Cl − anion, the most electronegative anion among the three investigated. This anomalous trend of ion pair dissociation was explained in terms of varying interaction strength between the solvent (CDCl 3 ) and the anions investigated.