Quantum Chemical Studies on The Efficiencies of Vinyl Imidazole Derivatives as Corrosion Inhibitors For Mild Steel

Abstract

The corrosion inhibition characteristics of two vinyl imidazole derivatives, ie., 2,4,5-triphenyl-1-vinyl-1H-imidazole (C1) and 2-(4-methoxyphenyl)-4,5-diphenyl-1-vinyl-1H-imidazole(C2), on mild steel has been studied using Density functional theory (DFT).Quantum chemical parameters such as EHOMO (highest occupied molecular orbital energy), ELUMO (lowest unoccupied molecular orbital energy), the energy gap(ΔE), hardness(η), Softness(S), dipole moment(μ), electron affinity(EA), ionization potential(IE), the absolute electronegativity (χ) , electrophilicity index(ω) and the fraction of electron transferred (ΔN) have been calculated using B3LYP/6-31G(d,p) basis set. The local reactivity has been studied through the Fukui and condensed softness indices in order to predict both the reactive centres and to know the possible sites of nucleophilic and electrophilic attacks. The obtained correlations and theoretical conclusions agree well with the experimental data.