Spectroscopic Investigation (FT-IR, FT-RAMAN, UV and NMR), NBO, NLO Analysis and Fukui Function of 2, 5-Dichloroaniline by DFT Calculations

The spectral characterization of 2,5Dichloro aniline (2,5 DCA) were carried out by using FT-IR, FT-Raman, the NMR and UV-Vis spectroscopic techniques. The simulated vibrational spectra of the molecule are compared with the experimental spectra. The structural optimization has been performed on the title molecule using HF and density functional theory (DFT) with basis sets 6-31+G(d,p) and 6-311++G(d,p). The optimized bond parameters of 2,5 DCA were compared with the experimental data of related molecule. Using Veda program, the vibrational wave number assignments were made on the basis of total energy distribution (TED) calculations. To study the intra-molecular charge transfers within the molecule, the Lewis (bonding) and Non-Lewis (anti-bonding) calculation was performed. The orbital gap of the molecule was determined from HOMO and LUMO calculations. The Non-linear optical properties of the molecule were studied using first hyperpolarizability calculation. The molecular electrostatic potential (MEP), chemical descriptors and thermo dynamical properties of the molecule have also been calculated and analysed. In addition, the Mulliken atomic charges and the 1 H and 13 C NMR chemical shift values of 2,5 DCA was calculated. Also the local reactivity of the molecule was studied using the Fukui function.