THE SPECTROSCOPIC ANALYSIS OF 2,4'-DIBROMOACETOPHENONE MOLECULEBY USING QUANTUM CHEMICAL CALCULATIONS

A spectroscopic investigation, used quantum chemical calculations, of 2,4'-dibromoacetophenone (2,4'-DBrA) molecule have been obtained in this paper. The calculations were supported the experimental results by IR, 1 H and 13 C NMR techniques. Geometrical parameters and optimized energies of 2,4'-DBrA molecule were performed by density functional theory (DFT) B3LYP method 6-311++G(d,p) basis sets. After the geometry optimization of 2,4'-DBrA the vibrational spectra were obtained for this structure. The fundamental vibrations were assigned to base on potential energy distribution (PED) of the vibrational modes by using VEDA 4 (Vibrational Energy Distribution Analysis) program. Density of states for total (TDOS), partial (PDOS) and also overlap population (OPDOS) analysis were obtained. 1 H and 13 C NMR chemical shifts were recorded by using the gauge-invariant atomic orbital (GIAO) method. Besides, electronic properties, such as HOMO and LUMO energies, were performed by time-dependent density functional theory (TD-DFT). Also, molecular electrostatic potential surface (MEPs) and thermodynamic properties were calculated for title molecule. The results are showed consistent with the obtained experimental results.