ab initio Study of Corrosion Inhibition Performance of Dibenzo-diaza-15-crown-5 and its Heterocyclic Analogs

摘要

The corrosion inhibition efficiency of dibenzo-diaza-15-crown-5(N)and its heterocyclic analogs containing O,S,and P atoms were investigated by ab initio MP2 calculations in aqueous phase.Heteroatoms have a significant role in the corrosion inhibition performance of the studied systems.The geometry parameter shows that the decrease of bond length corresponds to the increase of heteroatom covalent radius.It was revealed that phosphorus more easily donates its electrons to iron than other heteroatoms.Quantum parameters such as high occupied molecular orbital energies(E_(Homo))and the fraction of electrons transferred(AN)have a linear relationship with inhibition efficiencies(IE %).Analysis of second order interaction energies showed the highest back-donation contribution of metal to phosphorus.Theoretical calculations shows that corrosion inhibition increases in the sequence of oxygen < nitrogen < sulfur < phosphorus.