Geometry Optimization, Spectral Analysis, Molecular Electrostatic Potential Surface, and Nonlinear Optical Activity of 4-Methyl Anilinium Phenolsulfonate: a DFT Study

Abstract

The optimized molecular structure, vibrational frequencies and corresponding vibrational assignments as well as H-1 NMR and C-13 NMR chemical shifts of 4-methyl anilinium phenolsulfonate have been investigated using quantum chemical calculations. Obtained results, in particular, on the geometric structure, chemical shifts of H-1 and C-13, and vibrational frequencies are in good agreement with experimental data. The title compound was optimized using the BHandHLYP and WB97XD levels of density functional theory. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been studied using natural bond orbital analysis. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. Polarizability and hyperpolarizability values are calculated at the same levels in order to find the importance of the title compound in nonlinear optics. The molecular electrostatic potential has been simulated to demonstrate electrophilic and nucleophilic sides of the title compound.