A COMPUTATIONAL STUDY OF SUBSTITUENT EFFECT 1, 3, 4-THIADIAZOLE ON CORROSION INHIBITION

Abstract

A theoretical study of 1, 3, 4-thiadiazole with nine various derivatives in gaseous and aqueous phases was investigated by employing the density functional theory (DFT) at 6-311++(d, p) basis set and Becke’s three parameters hybrid exchange-correlation functional (B3LYP). The molecules are calculat-ed using quantum computational chemistry calculations such as Gaussian09 software. This paper is to determine the chemical reactivity for various heterocyclic organic compounds and to understand the process of corrosion inhibition. The quantum chemical properties such as the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), energy gap (∆E), dipole moment (μ), global hardness (η), global softness (S), electronegativity (χ), electrophilicity (ω), nucleophilicity (ɛ), chemical potential (CP) and electrons transferred from inhibitors to metal surface (ΔN) were calcu-lated. Dynamic simulation approximations to demonstrate the corrosion inhibition performances of studied inhibitors against the corrosion of 1, 3, 4-thiadiazole in the gaseous and aqueous phases can be given as 1<9<8<3<4<5<6<7<2 and1<3<9<8<3<4<5<6<7<2.