Molecular structural aspects of organic corrosion inhibitors: Experimental and computational insights

The design and development of efficient corrosion inhibitors require inputs from a wide variety of synthetic protocols, which is usually a time consuming and tedious process. The conventionally used experimental methods often turn out to be inadequate in the satisfactory effect of inhibitor structure on adsorption and corrosion inhibition. In recent years, the computational methods of density functional theory (DFT), Monte Carlo (MC) simulations, and the molecular dynamics (MD) simulations have shown that the structure and electronic properties play a major role in the inhibition performance. The inhibition efficiency can be governed by a number of factors, such as the presence of electronegative heteroatoms, size of the aromatic ring, hydrocarbon chain length, the presence of double bond, π-conjugation, and electron-donating/ withdrawing substituent groups. Sound knowledge of the relationship between the molecular structure of the organic corrosion inhibitors and their inhibition potential can facilitate the design and synthesis of highly effective corrosion inhibitors. This review article outlines a correlation between some of the molecular structural aspects of corrosion inhibitors with inhibitor performance.