Quantum Chemical Calculations on the Corrosion Inhibition Performance of Some Tetrazole Derivatives

In this study, a detailed quantum chemical studies of tetrazole (T) and some tetrazole derivatives such as 5-mercapto-1-methyl tetrazole (5-Mc-1-Me-T), 5-mercapto-1-phenyl tetrazole (5-Mc-1-Ph-T), 5-phenyl tetrazole (5-Ph-T) and 5-amino tetrazole (5-NH2-T) for neutral, and protonated forms in gas and water phase have been performed by using DFT/B3LYP/6–311++G(2d,2p) basis set. The quantum chemical parameters such as the highest occupied molecular orbital (E HOMO), the lowest unoccupied molecular orbital (E LUMO), energy gap (∆E), ionization energy (I), hardness (η), softness (σ), global electrophilicity (ω), chemical potential (ε), electronegativity (χ), Mulliken atomic charges, And so forth of molecules have been found and discussed relationship of these results with inhibition efficiency.