Evaluation of chemical reactivity and polarity of imidazolium-based ionic liquids using quantum chemical calculations

By using the DFT theory, the orbital energies of twenty-five ionic liquids were estimated. To comprehend their molecular stability and chemical reactivity, the orbital energy values, orbital energy gap (HOMO–LUMO energy gap), chemical hardness (η), chemical softness (S), electronegativity (χ), and electrophilicity index (ω) were computed. The interaction energies between all of the cations and anions under study were then computed and examined. Finally, using quantum chemical calculations, the molecular polarity of all 25 ionic liquids was examined using the sigma profile and sigma potential.

Using the lowest orbital energy of the molecules, HF/6-31G* level of theory quantum chemical calculation were carried out using the MOLDEN and GAUSSIAN03 software. The B3LYP DFT approach produced a COSMO file that contained the species optimal SCD.