Theoretical studies on the corrosion inhibition performance of three amine derivatives on carbon steel: Molecular dynamics simulation and density functional theory approaches

Inhibition efficiencies of three amine derivatives (diethylenetriamine I, triethylenetetramine II, and pen- taethylenehexamine III) on corrosion of carbon steel has been studied using the density functional the- ory method and molecular dynamic simulation in aqueous phase. Quantum chemical parameters such as E HOMO (highest occupied molecular orbital energy), E LUMO (lowest unoccupied molecular orbital energy), hardness ( η), polarizability ( α), dipole moment ( μ), total negative charges on atoms (TNC) and molecu- lar volume (MV) have been calculated at the B3LYP level of theory with 6-311 ++ G ∗∗basis set. Moreover, adsorption behavior of the inhibitor molecules on Fe (110) surface has been analyzed using molecular dy- namics simulation. The formation of the bonding and nonbonding interactions in systems of Fe-inhibitor molecules on Fe (110) surface followed the order III > II > I, which was in a good agreement with the ex- perimentally determined inhibition efficiencies. The formation of bonding and nonbonding interactions in systems of Fe-inhibitor was analyzed by the radial distribution functions (RDFs). In agreement with the experimental data, theoretical results showed that the order of inhibition efficiency is III > II > I.

Corrosion Inhibition DFT Molecular dynamics simulation Steel Amine derivatives