ABSTRACT
146In today’s world, the prevention of metallic corrosion is a very challenging job and would therefore be a mammoth task considering the enormous role of metals and their alloys in several industrial applications. To prevent solution state metallic corrosion suitable amount of organic molecules as inhibitor is widely used as additives to the corrosive solution. Among the organic inhibitors, different N, O, S donor Schiff base molecules are considerably used due to their low-cost starting precursor material, easy to follow synthetic route, and environmental friendly nature. Traditionally, scientists have identified new and prospective corrosion inhibitors either by the modifying the structure of the existing inhibitors or by following up the hardcore wet chemical synthetic routes, which in many instances have become laborious, expensive, time consuming and unable to reveal their microcosmic inhibition process. To overcome these shortfalls, in modern age, newly explored avenues like hardware and software advancements have opened up the door for powerful and worthy use of theoretical chemistry in corrosion inhibitory research domain following low-cost and timesaving processes. The use of computational chemistry in designing and development of organic corrosion inhibitors has been greatly enhanced due to the development of density functional theory (DFT). DFT is a modern tool that is capable enough to mostly predict accurately the relative order of inhibition efficiencies of concerned corrosion inhibitors, based on their molecular and electronic structure and reactivity indices. Furthermore, nucleophilic and electrophilic sites of the inhibitor molecules have also been determined from the analysis values of the DFT-based Fukui indices. Along with DFT, molecular dynamic (MD) simulation has also emerged as an important tool for investigating complex systems that actually need to be faced and experienced during corrosion prevention studies. MD simulation reasonably predicts the actual interfacial configuration of the surface adsorbed inhibitor molecules. Several parameters related to inhibition measurements like interaction energy and binding energy between the inhibitor molecule and metallic surfaces can also be calculated from MD simulation. From the obtained interaction energy and binding energy values it is possible to tell that which inhibitor molecule have superior adsorption ability on the metallic surfaces.
