Electric and Magnetic Evaluation of Aluminum–Magnesium Nanoalloy Decorated with Germanium Through Heterocyclic Carbenes Adsorption: A Density Functional Theory Study

Heterocyclic compounds with multiple bonds and heteroatoms of nitrogen, oxygen and sulfur can be notable as corrosion inhibitors for metal surfaces. In this work, Ge-doped Al–Mg nanoalloy has been investigated based on Langmuir adsorption and density functional theorey method (DFT) method. The partial electron density states (PDOS) have confirmed an obvious charge accumulation between the Al–Mg alloy and doped atom of Ge through the recognition of the conduction band region. The infrared (IR) spectrums for complexes of inhibitors adorbed on Ge-doped Al–Mg alloy have been reported in the frequency between 500–3500 cm–1 for (benzotriazole/2-mercaptobenzothiazole/8-hydroxyquinoline) → Al–Mg–Ge, and around 500–4000 cm–1 for 3-amino-1,2,4-triazole-5-thiol → Al–Mg–Ge with the sharpest peak approximately around 2000 cm–1, 3000 cm–1 for (benzotriazole/2-mercaptobenzothiazole/8-hydroxyquinoline) → Al–Mg–Ge and 2000 cm–1, and 4000 cm–1 for 3-amino-1,2,4-triazole-5-thiol → Al–Mg–Ge. Nuclear magnetic reonance (NMR) spectrocopy has focused on the intra-atomic and interatomic interactions with ONIOM model with three levels of high, medium and low by using LANL2DZ/6-31+G(d, p), semi-empirical and MM2 functions. Al–Ge(14), Al–Ge(19) and Al–Ge(21) in the Al–Mg–Ge alloy surface with the highest fluctuation in the shielding tensors of NMR spectrums generated by intra-atomic interaction direct us to the most influence in the neighbor atoms generated by interatomic reactions of N → Al, O → Al, S → Al through the coating and adsorbing process of Langmuir adsorption. This work indicated that proper monitoring of the coating mechanism by Langmuir adsorption can illustrate inhibiting the ternary aluminum nanoalloy of Al–Mg–Ge corrosion through an investigation of their structural and physicochemical analysis. Furthermore, it has been illusstrated the effect of the substitution of aluminum atoms in Al–Al nanosheet with Mg and Ge through resulted electric potential by using Nuclear quadrupole resonance (NQR) analysis.