Imidazolium based ionic liquids. 1-Ethanol-3-methyl-imidazolium dicyanoamide: Thermochemical measurement and first-principles calculations

The standard molar enthalpy of formation ΔfHm° (l) of the ionic liquid 1-ethanol-3-methylimidazolium dicyanamide has been determined at 298.15 K by means of combustion calorimetry. First-principles calculations of the enthalpy of formation in the gaseous phase have been performed for the ionic species using the composite G3(MP2) method. The combination of combustion calorimetry with the high-level quantum-chemical calculations allows to estimate the molar enthalpy of vaporization of the ionic liquid under study. It has been established, that the liquid phase enthalpy of formation of this ionic liquid presumably obeys the group additivity rules.

► We studied the ionic liquid 1-ethanol-3-methylimidazolium dicyanamide. ► Combustion calorimetry was used to derive enthalpy of formation in the liquid state. ► Composite G3(MP2) method used to compute enthalpy of formation in the gaseous phase. ► Enthalpy of vaporization was derived as the difference. ► The liquid phase enthalpy of formation presumably obey the group additivity rules.