Acid solutions are extensively used in industrial processes, creating a corrosive environment and reducing durability and efficiency of metallic materials. Nevertheless, the use of organic molecules is one of the techniques to prevent corrosion. In this work, the adsorption study of three chalcone derivatives (IM-A, IM-B and IM-F) in mild steel was performed in order to investigate the corrosion inhibition efficiency in HCl medium. Theoretical calculations were performed at the CPCM-B3LYP-D3/def2-TZVPP level in order to correlate the inhibitor efficiency with electronic parameters such as HOMO-LUMO gap and dipole moment. The efficiency order of IM-A &lt; IM-B &lt; IM-F was obtained in good agreement with experimental results. Calculations for the inhibitor adsorption on the iron surface were performed with Quantum ESPRESSO. Exchange-correlation energies were properly calculated using the (PBE) functional. The valence states plane wave basis cutoff energies were properly converged while the Vanderbilt ultrasoft pseudopotentials was used to describe the core electrons. In order to include the effect of the dispersive interactions, the DFT-D3 correction was considered in all calculations. The Brillouin zone was sampled using a Monkhorst-Pack k-point mesh of (8 x 8 x 8) for the bulk material and (2 x 2 x 1) for the slab construction. The Fe (110) is the most stable iron surface. Hence, a (6 x 6) Fe (110) supercell with a four-layers slab was constructed. In order to minimize the interaction between the surface slab and the periodic images, an equivalent of 20 Å vacuum thickness was used. The adsorption energy (EADS) of the inhibitor in the Fe (110) slab is defined by EADS = E(INHI+SLAB) -EINHI-ESLAB. The strong adsorption is confirmed by the EADS values, which lies at around -2.78 eV (-64.11 kcal/mol) in excellent agreement with thermodynamic parameters obtained experimentally. The adsorption study of the chalcone derivative IM-F performed by periodic calculations at the PBE-D3 level is valid for inhibitor efficiency evaluation, showing good agreement with experimental results.

Computational study of the adsorption of chalcone derivatives on Fe(110) surface

Macromolecular Chemistry: The Second Century

[Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing)

[How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf)

[Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.