A theoretical approach to understand the inhibition mechanism of steel corrosion with two aminobenzonitrile inhibitors

In this work, the adsorption behavior and corresponding inhibition mechanism of two aminobenzonitrile derivatives, e.g., 2-aminobenzonitrile (2-AB) and 3-aminobenzonitrile (3-AB), in aqueous acidic medium on steel surfaces have been investigated using quantum chemical calculations and molecular dynamics (MD) simulations. Quantum chemical parameters such as E-HOMO, E-LUMO, energy gaps (Delta E), the dipole moment (mu), the global hardness (eta), the softness (S), and the fraction of electron transfer from the inhibitor molecule to the metallic surface (Delta N) have been calculated and well discussed. Fukui indices analysis was performed to get local reactive sites of the studied inhibitor molecules. Furthermore, molecular dynamics simulations were applied to search for the most favorable adsorption configuration of the inhibitor over an iron (1 1 0) surface.