Two types of imidazole analogs, namely 1-((4RS,5SR)-2,4,5-tris(4-methoxyphenyl)-4,5-dihydro-1 H-imidazol-1-yl)ethan-1-one (TOIE) and (4SR,5RS)-2,4,5-tri(furan-2-yl)-4,5-dihydro-1 H-imidazole (TFMI), were probed as corrosion-inhibiting substances for carbon steel in hydrochloric acid (HCl) milieu by dint of potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), ultraviolet-visible spectroscopy (Uv-visible), and scanning electron microscopy (SEM), together with theoretical approaches. The findings reveal that anticorrosion performance depends on both temperature and concentration; it reached 94.9 % for TOIE and 89.2 % for TFMI at 0.001 M under 303 K, respectively, but it was 90.2 and 79.4 %, respectively, at 0.001 M under 333 K. Examination of PDP revealed that all imidazole analogs perform as mixed-type inhibitors. Additionally, the adsorption mode of imidazole analogs on carbon steel complies with the Langmuir adsorption isotherm and includes a chemisorption process. The surface (SEM) and milieu (UV–visible) analyses substantiate that corrosion protection happens as a result of imidazole molecules' adsorption at the carbon steel interface. The obtained quantum chemical indices, such as global softness, electron transfer fraction, and energy gap, together with Fukui indices, can give a good interpretation of the effectiveness of inhibition. Molecular dynamics simulations (MDS) discovered that the TOIE and TFMI molecules, in a flat manner, are adsorbed on carbon steel orbitals, thus giving rise to more effective adsorption and corrosion inhibition.
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