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The FTIR and FT-Raman spectra of 2-fluoro benzamide (2FBA) have been recorded in the region 4000-400 and 4000-100 cm(-1), respectively. The structuralanalysis, hydrogen bonding, optimized geometry, frequency and intensity of the vibrational bands of 2FBA were obtained by the density functional theory (DFT) with complete relaxation in the potential energy surface using 6-31G** basis set. The harmonic vibrational frequencies were calculated and the scaled values have been compared with experimental FTIR and FT-Raman spectra. The observed and the calculated frequencies are found to be in good agreement. The (13)C NMR spectra have been recorded and (13)C nuclear magnetic resonance chemical shifts of the molecule were also calculated using the gauge independent atomic orbital (GIAO) method and their respective linear correlations were obtained. The electronic properties, such as HOMO and LUMO energies, were performed by time-dependent DFT (TD-DFT) approach. The Mulliken charges, the values of electric dipole moment (μ) of the molecule were computed using DFT calculations. The change in electron density (ED) in the σ* antibonding orbitals and stabilization energies E(2) have been calculated by natural bond (NBO) analysis to give clear evidence of stabilization originating in the hyper conjugation of hydrogen-bonded interactions., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In the present work, we reported a combined experimental and theoretical study on molecular structure and vibrational analysis of 2,6-dichlorotoluene (DCT) and 2-chloro-6-fluorotoluene (CFT). FTIR and FT-Raman spectra of the title compounds in the solid phase are recorded in the region 4000-400 cm(-1) and 4000-50 cm(-1) respectively. The structural and spectroscopic data of the molecules in the ground state is calculated using Hartree-Fock (HF) and density functional methods (B3LYP) with 3-21 and 6-31G* basis sets. The DFT (B3LYP/31G*) calculations have been giving energies, optimized structures, harmonic vibrational frequencies, IR intensities and Raman activities. The study is extended to the HOMO-LUMO analysis to calculate the energy gap, ionization potential, electron affinity, global hardness, chemical potential and thermodynamic properties of DCT and CFT. A complete vibrational assignment aided by the theoretical harmonic frequency analysis has been proposed. The calculated HOMO and LUMO energies show the charge transfer occurs in the molecule. The harmonic vibrational frequencies have been compared experimental FTIR and FT-Raman spectra. The observed and calculated frequencies are found to be in good agreement. The complete vibrational assignments are performed on the basis of the Total Energy Distribution (TED) of the vibrational modes calculated with scaled quantum mechanical (SQM) method. (13)C NMR chemical shifts results are compared with the experimental values. The experimental spectra also coincide satisfactorily with those of theoretically constructed spectrograms., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The vibrational spectra of 4-bromo benzonitrile have been reported. The fundamental vibrational frequencies and intensity of vibrational bands were evaluated using density functional theory (DFT) with the standard B3LYP/6-311+G basis set combination and were scaled using various scale factors which yielded a good agreement between observed and calculated frequencies. The vibrational spectra were interpreted with the aid of normal coordinate analysis. The results of the calculations were applied to simulated infrared and Raman spectra of the title compound which showed excellent agreement with the observed spectra.