The application of molar surface Gibbs energy to predicting ILs' properties

Abstract 1-alky-3-methylimidazolium taurate ionic liquid, [C n mim]Tau ( n  = 3,4) were synthesized by neutralization method and were confirmed by 1 H NMR and 13 C NMR. Standard addition method was applied to determine the densities, surface tensions and refractive indexes for [C n mim]Tau ( n  = 3,4). By using Tong's vaporization enthalpy model, the vaporization enthalpies of [C n mim]Tau ( n  = 3,4) and some other ILs were estimated. The association enthalpies, Δ A H m 0 of them in gas phase were estimated. Combined g s with Lorentz–Lorenz equation, a semi-empirical surface tension predicting equation can be obtained. The surface tensions of [C n mim][Tau]( n  = 3,4), some other ILs and some molecular liquids were predicted. The predicted values are highly similar with the corresponding experimental ones. In current work, we put forward a new method for predicting Δ l g C p,m 0 ,which was used for [C n mim]Tau ( n  = 3,4) and other ILs. Our results are in the same order magnitude with Verevkin's, but ours are relatively higher.