DFT Study on Corrosion Inhibitory Effects of Three Substituted Triazole Derivatives on Iron Surface

Three derivatives of triazole, namely 5-amino 1,2,4-triazole, 5-ATA, and 5-amino-3-mercapto 1,2,4-triazole, 5 –AMT, and 5-amino-3-methyl thio 1,2,4-triazole,5-AmeTT, which are recently used as corrosion inhibitors for steel, were considered as corrosion inhibitors for the iron surface using density functional theory (DFT), at the B3LYP / 6-31G (d) level. Fukui and Four functions, EHOMO, ELUMO, Eg, and ΔN, are defined as the highest occupied molecular orbital energy, the lowest unoccupied molecular orbital energy, the energy gap between HOMO and LUMO, and a fraction of electron transfer, were calculated respectively. They were evaluated to predict the active reaction sites and the electrophilic or nucleophilic attack. Also, The mechanism of the corrosion reaction was investigated. The computational results were very close to the experimental results.