Spectroscopic characterization and natural bond orbital analysis of 2-(trifluoromethyl) phenylacetonitrile based on DFT calculations

Abstract

The experimental Fourier transform infrared (FT-IR) and Fourier transform Raman (FT-Raman) spectra of 2-(trifluoromethyl)phenylacetonitrile (2TFMP) have been recorded in the spectral region 4000‒400 cm⁻¹ and 3500‒100 cm⁻¹, respectively. Also the title molecule has been characterized by ¹³C NMR and ¹H NMR spectroscopes. The geometry optimization and frequency calculations have been performed at B3LYP/6-311+G (d,p) level. A detailed interpretation of FT-IR and FT-Raman spectra aided by the potential energy distributions (PEDs) for the calculated frequencies has been reported. Results of this study showed that there is a good correlation between the experimental and computational results. The HOMO-LUMO energy gap explains the charge transfer interactions in the molecule. NBO (natural bond orbital) computations have been utilized to evaluate the stabilities which occur from charge delocalization and inter-molecular interactions have been studied using DFT calculations.