**1. Introduction**

Corrosion is a natural process and also a universal phenomenon of metals. Corrosion is the deterioration of the metal in the presence of the surrounding environment by chemical or electrochemical means [1–10]. The corrosion of metals results into a huge loss of economy in the world [11–14]. There are various methods to reduce or prevent corrosion. The use of corrosion inhibitors is one of the ways to protect metal surfaces against corrosion [15–18]. In the early days, inorganic compounds such as nitrates, chromates, borates, silicates, chromates, phosphate, and molybdates were used as inhibitors for the prevention of corrosion [19–31]. Due to the toxic and environmental effects of that inorganic inhibitor, scientists start using environment friendly organic inhibitor for prevention of corrosion [32–35]. The organic compounds that contain mainly nitrogen, oxygen, sulfur phosphorus, and multiple bonds or aromatic rings in their structures act as corrosion inhibitors [36, 37]. Various heterocyclic aromatic compounds are studied as organic inhibitors [38–48]. It has been studied by various groups that carboxylate and amine of aliphatic compounds can be used as organic inhibitors [49–52].

In this article, there will be a detailed study of organic compounds as inhibitors and their computational and theoretical studies will be explained. There are various reviews papers on molecular modeling of compounds as corrosion inhibitors by

various groups. The DFT and MD s simulation studies about adsorption of the organic corrosion inhibitors and the metal surface in various corrosive environments.
