A combined experimental and computational investigation of excess molar enthalpies of (nitrobenzene + alkanol) mixtures

Abstract

Excess molar enthalpies (HmE) for the binary mixtures of {(nitrobenzene+ethanol), 1-propanol, 2-propanol, 1-butanol and 2-butanol} have been measured over the entire composition range at ambient pressure (81.5kPa) and temperature 298K using a Parr 1455 solution calorimeter. From the experimental results, the excess partial molar enthalpies (HiE) and excess partial molar enthalpies at infinite dilution (HiE,∞) were calculated. The excess molar enthalpies (HmE) are positive for all {nitrobenzene (1)+alkanol (2)} mixtures over the entire composition range.A state-of-the-art computational strategy for the evaluation of excess partial molar enthalpies at infinite dilution was followed at the M05-2X/6-311++G∗∗ level of theory with the PCM model. The experimental excess partial molar enthalpies at infinite dilution have been compared to the computational data of the ab initio in liquid phase. Integrated experimental and computational results help to clarify the nature of the intermolecular interactions in {nitrobenzene (1)+alkanol (2)} mixtures. The experimental and computational work which was done in this study complements and extends the general research on the computation of excess partial molar enthalpy at infinite dilution of binary mixtures.