A DFT study on substituent effects on iron corrosion inhibition capability of indole derivatives

Tóm tắt

The corrosion inhibition activity of indole derivatives has been systematically examined by calculating quantum chemical parameters including energy of the highest occupied molecular orbital, energy of the lowest unoccupied molecular orbital, energy difference, molecular hardness, molecular softness, and the number of electrons exchanged between the metal and the corrosion inhibitor at the B3LYP/6-311++G (d,p) level of theory. The results demonstrate that derivatives containing the electron-donating groups exhibit superior efficiency in inhibiting iron corrosion compared to indole. Additionally, an investigation into the corrosion inhibition ability of derivatives containing the NH₂ group reveals that 6-NH₂-indole emerges as the most effective inhibitor, boasting an efficiency value of 97.11%. These calculated outcomes align with previously studied experimental results, underscoring the remarkable corrosion resistance of derivatives containing electron-donating groups.