Molecular structure and vibrational spectroscopic investigation of 4-chloro-4′dimethylamino-benzylidene aniline using density functional theory

The Fourier Transform Raman and infrared spectra of the crystallized 4-chloro-4′dimethylamino-benzylidine aniline (CDMABA) have been recorded in the region 3500–200 cm−1 and 4000–400 cm−1, respectively. The geometry optimization, electrostatic potential surface and vibrational wavenumbers with Raman scattering activities and infrared absorption intensities have been investigated by density functional theory (DFT) method using 6-311++G(d,p) basis set and Becke’s three-parameters hybrid functional (B3LYP). The calculated molecular geometry has been compared with the experimental data obtained from XRD. The assignments of the vibrational spectra have been carried out with the aid of normal coordinate analysis (NCA). The natural bond orbital analysis (NBO) has been performed in order to study the intramolecular bonding, interactions among bonds and delocalization of unpaired electrons. The electrostatic potential surface mapped with isodensity surface has been obtained.