DFT and NBO Studies of Stability, Electronic, and Structural Features of the 2-fluoroacetaldehyde Conformers

Abstract

In this investigation, the stability of the keto-enol forms and conformers of 2-fluoroacetaldehyde was investigated by LC-wPBE, B3LYP and M06-2X functionals and 6-311++G(d,p) basis set. The total energy, the energies of frontier orbitals, HOMO-LUMO gaps and total dipole moment of these molecules were estimated. These calculations show that more stability of the keto form in compared to enol form. Calculations at the LC-wPBE/6-311++G(d,p) level of theory reveal the more stability of I-conformer in compared to other conformers. Natural bond orbital (NBO) analysis was applied for illustrating the negative hyperconjugative effect on the conformers. In the basis of NBO analysis, the LP (O2) *(C-H) and LP (O2) *(C-C) interactions were responsible of the negative hyperconjugation in the examined compounds. The interaction energy, off-diagonal elements, and total steric energy values of these interactions were reported.