Revealing the anti-corrosion mechanism of fluconazole by experimental and theoretical studies

Through techniques such as electrochemical impedance spectroscopy and open circuit potential, the protective behavior of fluconazole against the mild steel corrosion process in neutral medium was evaluated. Best-fitted adsorption isotherm was the Frumkin model respect to Langmuir, which implies a multilayer protective film formation with lateral attraction between the adsorbed inhibitor molecules on mild steel surface. To document the protective mechanism, DFT computations and QTAIM analysis were carried out. The results, showed that the stability of the protection film is attributed to the flu-flu and flu-water clusters formation which, are stabilized by O-H center dot center dot center dot N, O-H center dot center dot center dot O, C-H center dot center dot center dot N, C-H center dot center dot center dot O, C-H center dot center dot center dot F hydrogen bonds, as well as p-stacking. Altogether, the results reported here suggest that the fluconazole is adsorbed on the metal surface demonstrating that electrostatic interactions are the most relevant in the corrosion process.