Imidazolium-based ionic liquids containing FAP anion: Thermodynamic study

© 2019 Elsevier B.V. New experimental vapor pressures and vaporization enthalpies of the ionic liquids (ILs) [C2mim][FAP], [C4mim][FAP], and [C6mim][FAP] with [FAP] = tris(pentafluoroethyl)trifluorophosphate have been measured by the Langmuir method combined with the Quartz Crystal Microbalance. Linear dependence of vaporization enthalpies on alkyl chain length was observed. Gas-phase enthalpies of formation of ILs were calculated by quantum chemistry. Solution enthalpies of ILs available from the literature were used for calculation the aqueous enthalpy of formation of the ∆fHom(FAPaq−) anion in combination with quantum-chemical results. These results will facilitate chemical engineering calculations of processes involving ILs