Experimental and theoretical investigations of benzamide oxime

The FT–IR (4000–400 cm−1) and FT–Raman (4000–100 cm−1) spectral measurements of benzamide oxime and complete assignments of the observed spectra have been proposed. Ab initio and DFT calculations have been performed giving energies, optimized structures, harmonic vibrational frequencies, depolarization ratios, IR intensities, Raman activities and atomic displacements. Furthermore, force field calculations have been performed by normal coordinate analysis. Force field calculations showed that several normal modes are mixed in terms of the internal coordinates. A complete assignment of the observed spectra, based on spectral correlations, electronic structure calculations and normal coordinate analysis, has been provided.

Graphical abstractA complete assignment analysis of the observed FTIR and FT-Raman spectra, based on spectral correlations, electronic structure calculations and normal coordinate analysis, has been proposed. Ab initio and DFT calculations have been performed giving energies, optimized structures, harmonic vibrational frequencies, depolarization ratios, IR intensities, Raman activities and atomic displacements. The oxime group has an E configuration with the dihedral angle C1–C7–N8–O9 = −179.999°.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A complete assignment and analysis of the observed FTIR and FT-Raman spectra of benzamide oxime has been proposed. ► Ab initio and DFT calculations have been performed giving energies, optimized structures, harmonic vibrational frequencies, depolarization ratios, IR intensities, Raman activities and atomic displacements. ► The geometry of the benzamide oxime molecule under investigation is considered by possessing CS point group symmetry. ► The oxime group has an E configuration with the dihedral angle C1–C7–N8–O9 = −179.999°.