Electronic structure and quantum chemical analysis of the corrosion inhibition efficiency of quinoxalines

A theoretical investigation of the corrosion inhibition effectiveness of 1-[4-acetyl-2-(4-chlorophenyl) quinoxalin-1(4H)-yl] acetone (Q1), 2-(4-(2-ethoxy-2-oxoethyl)-2-p-tolylquinoxalin-1(4H)-yl) acetate (Q2) and 2-(4-methylphenyl)-1,4-dihydroquinoxaline (Q3) was evaluated by using quantum chemical parameters from density functional theory (DFT) with 6–311++ G (d, p) basis set at B3LYP level. Several quantum chemical parameters were determined to evaluate the array of selected molecules such as (ELUMO), energy gap (ΔE), (EHOMO), hardness, ionization potential, electronegativity, dipole moment (μ), the fraction of the electrons transferred from the inhibitor to the metal surface (ΔN), the softness (σ) and the total energy (TE). Theoretical data were found to confirm experimental results. By using these different quantitative chemical parameters to determine corrosion inhibition efficiency, we compare the results of the recent corrosion investigation of these inhibitors. [Display omitted]