Molecular Structure, Spectroscopic Investigation, DFT Calculations and Other Biomolecular Properties of 1,2,3-trichloro-4-nitrobenzene

摘要

The experimental FTIR (4000–400 cm-1) and FT-Raman spectra (3500-50 cm-1) of 1,2,3-trichloro-4-nitrobenzene (TCNB) in solid phase have been recorded. The density functional theoretical (DFT) computations were performed at the B3LYP quantum chemical method with 6-31+G(d,p) and 6-311++G(d,p) basis sets to derive the optimized geometric parameters and vibrational frequencies. The theoretical vibrational spectral characteristics of TCNB are compared with the experimental results. The assignments of the vibrational frequencies have been confirmed by total energy distribution (TED) analysis. The possible electronic transitions are determined by HOMO–LUMO orbital shapes and their energies using the same theoretical calculations. TCNB exhibited good nonlinear optical activity and was much greater than that of urea. The charge density distribution and site of chemical reactivity of the molecule have been obtained by molecular electrostatic potential (MESP) studies. In addition, natural bond orbital (NBO), Mulliken charges and thermodynamic properties were also investigated.