Prediction of the steel corrosion inhibition potential of tryptophan derivatives based on quantum chemical parameters

Tóm tắt

The corrosion inhibition performance of tryptophan derivatives was investigated using density functional theory calculations. Quantum chemical descriptors were analyzed to assess electron-donating and electron-accepting abilities and interaction tendencies with the Fe surface. Most electron-donating substitutions produced favorable changes in the computed descriptors, although the magnitude and direction of these effects depended on substituent type and position. Among the hydroxyl-substituted derivatives, 4-OH-TN and 6-OH-TN showed the highest estimated inhibition efficiency of 93.61%, while 6-OH-TN exhibited a favorable overall combination of quantum chemical descriptors. Introducing stronger electron-donating groups at the C6 position further improved the predicted inhibition performance. Among the C6-substituted derivatives, 6-NH₂-TN exhibited the most favorable electronic descriptors and the highest estimated inhibition efficiency of 98.75%. These results highlight the roles of substituent type and position in modulating the predicted corrosion inhibition performance of tryptophan derivatives.