Theoretical Investigation of 6-(3,3,4,4,4-Pentafluoro-2-Hydroxy-1-Butenyl)-2,4-Dimethoxy-Pyrimidine Molecule

Abstract

In this paper, we report a theoretical study on conformational, natural bond orbital (NBO) and nonlinear optical (NLO) analysis, molecular geometry, vibrational frequencies, 1H and 13C NMR chemical shifts values of the title molecule in the ground state calculated with the help of Density Functional Theory (DFT-B3LYP/6-311++G(d,p)) and Hartree–Fock (HF/6-311++G(d,p)) methods. In this study, conformational analysis has been calculated using Hartree–Fock (HF) at 6-31G level for the title molecule. The existence of intramolecular hydrogen bonding interactions, and various molecular parameters has been investigated by means of the natural bonding orbital (NBO) analysis. The optimized geometric parameters, vibrational frequencies, 1H and 13C NMR chemical shifts values are compared with experimental values of the investigated molecule. To understand this phenomenon in the context of molecular orbital picture, we examined the highest occupied molecule energy level (EHOMO), the lowest unoccupied molecule energy level (ELUMO), the energy difference (\({\Delta E)}\) between EHOMO and ELUMO, electronegativity (\({\chi )}\) , hardness (\({\eta )}\) and softness (S) calculated by HF/6-311++G(d,p) and B3LYP/6-311++G(d,p) levels. The calculated HOMO and LUMO energies show that the charge transfer occurs within the molecule. It has also been calculated thermodynamic parameters, molecular surfaces, Mulliken charges and atomic polar tensor-based charges of the investigated molecule. Finally, the calculated results were applied to simulate infrared and NMR spectra of the investigated molecules which showed good agreement with experimental ones.