A Theoretical Study on Chemically Elegant Proton Pump Inhibitors in Search of Novel Green Corrosion Inhibitors

Abstract

Aluminum and its alloys exhibit remarkable corrosion resistance property due to its ability to form a tightly adhered, invisible protective oxide layer. Although this layer prevents or decelerates the corrosion of aluminum in HCl solution under certain conditions, they have to be used with inhibitors in very extreme circumstances of industrial applications. However, traditional inhibitors normally include environmentally hazardous substances, and therefore the development of novel green inhibitors becomes an important and vogue research subject. In this work, quantum chemical calculation approach was deployed and the density functional theory at B3LYP/6-311G++(d,p) basis set level calculations were performed on PPI drugs for the purpose of investigating the relation between their molecular structure and inhibition efficiency. Quantum chemical parameters such as the highest and lowest occupied molecular orbital energy, energy gap, dipole moment, electronegativity and hardness were calculated and a favorable correlation between the theoretical data and the experimental results was found.