DFT (B3LYP/LanL2DZ and B3LYP/6311G+(d,p)) comparative vibrational spectroscopic analysis of organic–inorganic compound bis(4-acetylanilinium) tetrachlorocuprate(II)

The organic–inorganic salt, bis(4-acetylanilinium) tetrachlorocuprate(II), was synthesized and characterized by means of FT-IR (4000–400 cm−1) and Raman (3500–50 cm−1) in solid phase. The structure of [C8H10NO]2CuCl4 compound which was optimized by density functional theory (DFT) using B3LYP method showed that the calculated values obtained by B3LYP with LanL2DZ and 6311G+(d,p) basis sets are in better agreement with the experimental data. The computed vibrational frequencies were scaled by different scale factors to yield a good agreement with the experimental vibrational frequencies. The latter have been discussed on the basis of quantum chemical DFT calculations using the B3LYP/6311G+(d,p) and B3LYP/LanL2DZ method approach in gas phase. Besides, the effects due to the substitutions and the intermolecular interactions were investigated. The comparative analysis of the Raman spectra of the title compound with that of the free ligand was also discussed. The geometries and normal modes of the vibrations obtained from B3LYP/6311G+(d,p) calculation are found to be in good agreement with the experimentally observed data. The complete vibrational assignments and analysis of the observed fundamental bands of molecule were carried out.