FT-IR and FT-Raman vibrational analysis, ab initio HF and DFT simulations of isocyanic acid 1-naphthyl ester

Abstract

The Fourier transform infrared and Fourier transform Raman spectra of isocyanic acid 1-naphthyl ester (C(11)H(7)NO) [ICANE] are recorded in solid phase, the harmonic vibrational frequencies, infrared intensities, Raman activities, bond length, bond angle and dihedral angle are calculated by HF and DFT methods by using different basis set. A detailed vibrational spectral analysis has been carried out and assignments of observed fundamental bands have been proposed on basis of peak positions and relative intensities. The scaled theoretical frequencies showed very good agreement with experimental values. A detailed interpretations of the infrared and Raman spectra of isocyanic acid 1-naphthyl ester are reported, the theoretical spectra for infrared and Raman spectrum of title molecule have been constructed. The effect due to the substitutions of isocyanato group is also investigated. A study on the electronic properties, such as excitation energies and wavelengths, are performed with different solvent by time-dependent DFT (TD-DFT) approach. HOMO and LUMO energies are calculated that these energies show charge transfer occurs within the molecule.