Molecular structure, NBO analysis and vibrational spectra of 2-hydroxy-3-methoxy-N-(2-chloro-benzyl)-benzaldehyde-imine by ab-initio and density functional theory

Quantum chemical calculations have been performed to compute optimized molecular geometry, atomic charges and vibrational characteristics for 2-hydroxy-3-methoxy-N-(2-chloro-benzyl)-benzaldehyde-imine (C15H14O2NCl) in the ground state using restricted Hartree-Fock (RHF) and density functional theory (DFT) methods with 6-31+G** basis set. NBO analysis is also performed. The IR and Raman spectra are obtained and assigned by vibrational analysis and found to be reliable compared with the experimental results. Theoretical vibrational spectra of the title compound have been interpreted by means of potential energies distributions (PEDs) using MOLVIB program. In addition, the results show that there exist C-H...N and O-H...O hydrogen bonds in the title compound, which play a major role in stabilizing the molecule and are confirmed by the natural bond orbital analysis. The Mulliken population analysis on atomic charges has also been calculated.