Condensed phase behaviour of ionic liquid–benzene mixtures: congruent melting of a [emim][NTf2]·C6H6 inclusion crystal

Abstract

The solid–liquid phase diagram of the (1-ethyl-3-methylimidazolium bis{(trifluoromethyl) sulfonyl} amide + benzene) system was determined and allowed us to identify and characterize an equimolar inclusion compound, [emim][NTf₂]·C₆H₆, with a congruent melting temperature: this type of behaviour, reported here for the first time, together with the X-ray structure of the inclusion compound lays emphasis upon the interactions that are responsible for the existence of liquid clathrates at higher benzene concentrations.