Quantum Chemical Study for Structure, Electronic and NLO Properties of 2-Amino-4-nitrotoluene and 2-Amino-5-nitrotoluene

Abstract

Molecular structure, molecular orbital energies; and global reactivity parameters of 2-amino-4-nitrotoluene (2A4NT) and 2-amino-5-nitrotoluene (2A5NT) were studied using DFT/B3LYP/6-311++G(d,p) level of theory. The energy difference between HOMO and LUMO was found to be 3.35 eV and 3.41 eV, respectively. Computed electrophilicity index values (ω = 12.63 and 14.61) demonstrate that the molecules are strong electrophile. The reactive sites and charge distribution of the compounds were analyzed by MEP surface. The non-linear optical activity of title compounds was studied by calculating the values of total dipole moment and mean first order hyperpolarizability. The natural charges of the molecules were obtained from NBO analysis; and the entire atomic charges were acquired by means of Mulliken study. The NMR (13C & 1H) theoretical chemical shifts were predicted by using GIAO approach in DMSO-d6 solvent. The values of energy, oscillator strength and absorption wavelength were computed from the UV-Vis spectra using TD-DFT method.