Quantum chemistry studies of triatomic heterocyclic compounds

Abstract

Four triatomic heterocyclic compounds were optimized extensively by utilizing Gaussian94 program package at the B3LYP/6-311++G** level. The computed results are in good agreement with the experimental values, which shows that the Density Functional Theory (DFT) method is stable and reliable for optimizations of heterocyclic compounds.Based on this,some thermodynamic parameters and the vibrational frequencies were got and the vibrational analysis was carried out.