Surface Tension of Ionic Liquids Analogues Using the QSPR Correlation

Deep eutectic solvents (DESs) are mixture complexes being introduced in many applications due to their favorable physicochemical characteristics. However, due to the lack of experimental data, prediction of their physical properties is challenging. One of the important physical properties that provides considerable insight of the molecular influence on intensity of interactions in the mixture is the surface tension. In this work, the QSPR prediction method was employed to predict the DESs surface tension. The parachors of selected DESs based on ammonium and phosphunium salts were determined experimentally and also calculated from the molecular structure of their constituting components using available parachor contribution data for neutral compounds. The results showed that the calculated and experimental parachors of DESs were notably comparable and the parachor contribution data developed for neutral compounds can be successfully utilized for DESs. The calculated parachors were employed to predict the surface tension using their experimental densities values.