Corrosion Inhibition of Steel in Acidic Medium by Eugenol Derivatives: Insight from Density Functional Calculation

Corrosion inhibition properties of eugenol derivatives have been elucidated by means of density functional theory at B3LYP/ 6-31G(d) level of theory. The quantum chemical parameters including the highest occupied molecular orbital (EHOMO) and lowest unoccupied molecular orbital (ELUMO), gap energy (∆Egab), ionization potential (I), electron affinity (A), the absolute electronegativity (χ), hardness (η), softness (σ), and the fraction of electron transferred (ΔN) are studied for investigating the corrosion inhibition performance of acetyleugenol derivatives. Effect of electron donating and withdrawing groups has been studied on the corrosion inhibition performance of acetyleugenol derivatives. The NH2 (electron donating substituent) exhibits the highest inhibition efficiency, whereas the NO2 (electron withdrawing substituent) exhibits the lowest inhibition efficiency. This study would have a significant contribution in designing highly potential eugenol based corrosion inhibitors.