Computational (DFT) Simulations for Comparative Prediction of Chemical Reactivity and Stability of Linoleic and Stearic Acid Molecules

Abstract

The frontier molecular orbitals (HOMO and LUMO) of stearic and linoleic acids were simulated using density functional theory (DFT) at the B3LYP/6-31G*basis set level with the use of Spartan '10 wave function software with a view to comparing their reactivity and stability based on some theoretically calculated parameters. The total energy (absolute values), energy gap between the HOMO and LUMO, EHOMO, total energy and global hardness values of stearic acids were found to be higher than those of linoleic acid while values of ELUMO, dipole moment and global softness calculated were higher for linoleic acid than stearic acid. Results show that linoleic acid would have higher reactivity and lower stability than stearic acid due to its relative softness. Spectroscopic investigation gives similar spectral positions with an additional infra-red vibrational frequency at around 3000 cm-1 for linoleic acid.