Abstract: The structural characteristics of imidazoline derivatives were analyzed by quantum chemistry method. Three imidazoline derivatives, imidazoline, methyl imidazoline and nitrophenyl imidazoline, were designed. The molecular structure, charge distribution, orbital energy, binding energy of coordination with Fe atom and the structural characteristics of coordination compounds were calculated, the intermolecular force and binding energy between Fe atom and different imidazoline derivatives was analyzed, and three corresponding compounds were synthesized and their corrosion inhibition performance was evaluated. The results showed that the order of corrosion inhibition performance of imidazoline corrosion inhibitors from strong to weak was methyl imidazoline > imidazoline > nitrophenyl imidazoline. The stronger the electron-donating ability of the substituent in the imidazoline derivative molecule, the smaller the frontier molecular orbital energy difference between the imidazoline derivative molecule and the Fe atom, the better the effect of the coordination adsorption on the metal surface, and the better the corrosion inhibition performance of the corrosion inhibitor was.

Key words: imidazoline, quantum chemistry, rust inhibitor