Spectral analysis, vibrational assignments, NBO analysis, NMR, UV–Vis, hyperpolarizability analysis of 2-aminofluorene by Density Functional Theory

Abstract

In this present investigation, the collective experimental and theoretical study on molecular structure, vibrational analysis and NBO analysis has been reported for 2-aminofluorene. FT-IR spectrum was recorded in the range 4000–400cm−1. FT-Raman spectrum was recorded in the range 4000–50cm−1. The molecular geometry, vibrational spectra, and natural bond orbital analysis (NBO) were calculated for 2-aminofluorene using Density Functional Theory (DFT) based on B3LYP/6-31G(d,p) model chemistry. 13C and 1H NMR chemical shifts of 2-aminofluorene were calculated using GIAO method. The computed vibrational and NMR spectra were compared with the experimental results. The total energy distribution (TED) was derived to deepen the understanding of different modes of vibrations contributed by respective wavenumber. The experimental UV–Vis spectra was recorded in the region of 400–200nm and correlated with simulated spectra by suitably solvated B3LYP/6-31G(d,p) model. The HOMO–LUMO energies were measured with time dependent DFT approach. The nonlinearity of the title compound was confirmed by hyperpolarizabilty examination. Using theoretical calculation Molecular Electrostatic Potential (MEP) was investigated.