Chapter12 - Computational methods of corrosion assessment

Abstract

Nowadays, computational modeling carried out using density functional theory, molecular dynamics (MD), and Monte Carlo (MC) simulations are widely used to support the weight loss and electrochemical results and to describe the interaction between metal surface and corrosion inhibitors. Computational modelings successfully describe the effect of different substituents on the corrosion inhibition potentials of organic corrosion inhibitors. Obviously, these techniques provide various indices including energy of highest occupied molecular orbital (EHOMO), lowest unoccupied molecular orbital (ELUMO), energy bandgap (ΔE: ELUMO−EHOMO), hardness (η), softness (σ), electronegativity (χ), fraction of electron transfer (ΔN), binding energy (Ebinding), and adsorption energy (Eads), etc., in the term of which interaction of organic compounds to be used as corrosion inhibitors can be described. Using localized regions in FMOs, molecular sites responsible for charge sharing (donation and retro-donation) can be easily accessed. Nature and effectiveness of metal–inhibitor interaction can also be simulated using MD and/or MC methods. More so, MD and MC simulations also provide pictorial illustration of the orientation of organic corrosion inhibitors on metallic surfaces. The present chapter describes the implementation of common computational techniques in corrosion monitoring.