In the context of copper corrosion passivation, the adsorption of benzotriazole (BTAH) and its derivatives: 5-Methyl, 5-Amine, 1-Amine, 1-Methyl on a Cu(111) surface was investigated using periodic density functional (DFT) calculations. The results were contrasted with experimental ASTM protocols. Adsorption of BTAH and radical (BTA●) forms, as well as solvent effect were evaluated. The Cu-N interaction provides stable complexes with adsorption over top sites. Radical forms yielded more stable complex. Their adsorption energies correlate with the substituent position and electronic features. And finally, a strong interaction was obtained when the charge transfer goes from surface to adsorbate.