Theoretical evaluation of the corrosion inhibition performance of 1,3-thiazole and its amino derivatives

The corrosion inhibition performances of three corrosion inhibitors on mild steel in acidic medium, namely 1,3-thiazole (TA), 2-amine-1,3-thiazole (2-ATA), and 4-amine-1,3-thiazole (4-ATA), were theoretically evaluated using quantum chemistry calculations and molecular dynamics simulations both in gas phase and aqueous phase. The frontier orbital energy, global activity, and Fukui indices were studied. Adsorption energy of corrosion inhibitors on iron surface was calculated. Furthermore, a prediction of iron crystal morphology was performed, and the surface energies were obtained. The results indicate that Fe (1 1 0) surface possesses the lowest surface energy. 4-ATA shows the highest reaction activity among the three molecules. The binding energies of the corrosion inhibitor molecules and iron surface follow the order 4-ATA > 2-ATA > TA.