Structure–Property Relationships in Ionic Liquids: A Study of the Anion Dependence in Vaporization Enthalpies of Imidazolium‐Based Ionic Liquids

Abstract

Vaporization enthalpies for a series of ionic liquids (ILs) with the common cation 1-ethyl-3-methylimidazolium [C(2)mim] and different counter anions are determined using a quartz crystal microbalance method. Dependences of vaporization enthalpies on physicochemical parameters specific for cation and anion interactions are revealed. A linear relation between enthalpies of vaporization and the intermolecular vibrational frequencies is observed and suggested for calculation of unknown ILs. A simple group-contribution method is developed for prediction of vaporization enthalpies of alkyl imidazolium-based ILs.