Estimation physicochemical property of ionic liquid [Smim][HSO4] by semi-empirical method

Ionic liquid (IL) [Smim][HSO4] (1-heptyl-3-methyl-imidazolium hydrogen sulfate) was synthesized and characterized. The density and surface tension of the IL were determined in temperature range 293.15 to 343.15 ± 0.05 K. Some physical–chemical properties of the IL have been calculated or estimated by the empirical methods. In terms of Glasserʹs theory, the standard molar entropy and lattice energy of the IL were estimated. Using Kaboʹs method, the molar enthalpy of vaporization of the IL, ΔlgHm0 (298 K), was estimated. According to the interstice model, the thermal expansion coefficient of IL, α, was calculated and in comparison with experimental value, their magnitude order is in good agreement.