Inhibitory performance of (<i>E</i>)-4-(3,4,5 trimethoxyphenyl)but-3-en-2-one crystal toward carbon steel corrosion in acid medium by practical and theoretical approaches

(<i>E</i>)-4-(3,4,5 Trimethoxyphenyl)but-3-en-2-one (TMBN) role as a carbon steel (C/S) corrosion crystal inhibitor in 1 M HCl was scrutinized <i>via</i> multiple techniques: weight loss measures, UV-visible spectroscopy, electrochemical analyses, SEM, and EDX for surface observations, as well as theoretical computation. The inhibition efficiency, as measured by all techniques, stays coherent and demonstrates an enlargement with higher inhibitor concentrations. TMBN displayed better inhibition performance for C/S corrosion in the acidic milieu, achieving an astonishing 98.1% inhibition at 0.001 M. The polarization approach demonstrated that TMBN operated as a mixed-type inhibitor, effectively hindering both anodic and cathodic processes simultaneously. The interaction between TMBN and C/S orbitals adheres to a Langmuir adsorption model, and its inhibition mechanism is facilitated by chemical interactions. As a result, the thermodynamic and kinetic variables were estimated and thoroughly discussed. The UV-visible spectrum ascertains the setting up of a complex between the TMBN and the iron ions present in the acidic milieu, while the SEM/EDX and contact angle display the shaping of an adsorbed film at the C/S facade. Density functional theory and molecular dynamic simulations were assembled to establish the correlation between theoretical variables and practical outcomes.