Structural insights, spectral, flourescence, Z-scan, C-H…O/N-H…O hydrogen bonding and AIM, RDG, ELF, LOL, FUKUI analysis, NLO activity of N-2(Methoxy phenyl) acetamide

Abstract

Quantum chemical calculations of geometries and vibrational wavenumbers of N-2(methoxy phenyl)acetamide(N2MPA) in the ground state were carried out by using density functional theory (DFT/B3LYP) method with 6-31G (d,p) basis set. The scaled harmonic vibrational frequencies have been compared with experimental FT-IR spectra. Theoretical vibrational spectra of the title compound were interpreted by means of potential energy distributions (PEDs) using MOLVIB program. The experimental 1H and 13C NMR chemical shifts were investigated and then compared with computed NMR data using the gauge – invariant atomic orbital (GIAO) method. The optical nature of the grown crystal was evaluated by using the UV-Vis optical transmittance spectrum. The lower wavelength absorption range and various optical constant for instance, energy band gap, absorption and extinction coefficient, refractive index, susceptibility and Urbach energy values were evaluated. The colourless crystal of N2MPA was grown by slow-evaporation technique. The nonlinear optical (NLO) properties of N2MPA have been investigated using Z-scan technique. The emission behavior of N2MPA was analyzed by fluorescence spectral analysis. Thermal stability of N2MPA was studied by TG-DTA analysis. The HOMO and LUMO energy levels are constructed and the corresponding frontier energy gaps are determined to realize the charge transfer within the molecule. The molecular electrostatic potential(MESP), natural bond orbital(NBO) analysis and topological analysis such as electron localization function(ELF), reduced density gradient(RDG), localized orbital locator(LOL), atoms in molecule(AIM) and FUKUI function analysis have been used to evaluate the intermolecular interaction, especially the hydrogen bonds. Fingerprint plots of Hirshfeld surfaces were used to locate and analyze the percentage of hydrogen bonding interactions.