DFT AND VIBRATIONAL SPECTROSCOPIC STUDY ON PYRIMIDINE DERIVATIVE INSECTICIDE

Abstract

A complete vibrational analysis of (6-methyl-2-thiophen-2-ylpyrimidin-4-yl) N,N-dimethylcarbamate (MTPD) was performed by using theoretical information using density functional theory based on scaled quantum chemical approach. The structural and spectroscopic data of the molecule were obtained from B3LYP with 6-31G(d) basis set calculations. The complete vibrational distributions were performed on the basis of the potential energy distribution (PED) of the vibrational energy distribution analysis (VEDA 4) program. The stable geometry of the compound has been determined from potential energy surface scan. The calculated HOMO and LUMO energies show that charge transfer occur within the molecule. Comparison of simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the modes of vibration. Natural charge analysis and molecular electrostatic potential (MESP) has been calculated.