Structure and vibrational frequencies of 1-naphthaldehyde based on density functional theory calculations

ArticleinSpectrochimica Acta Part A Molecular and Biomolecular Spectroscopy 69(2):528-33 · March 2008with7 Reads
DOI: 10.1016/j.saa.2007.04.031 · Source: PubMed
The mid and far FTIR and Raman spectra were measured in the liquid state. The fundamental vibrational frequencies and intensity of vibrational bands were evaluated using density functional theory (DFT) and standard B3LYP/6-311+G** basis set combination. The vibrational spectra were interpreted, with the aid of normal coordinate analysis based on a scaled quantum mechanical (SQM) force field. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes. Unambiguous vibrational assignment of all the fundamentals was made using the total energy distribution (TED).
    • "The calculated values at 1755, 1728, 1706, 1613 and 1599 cm À1 for HF and 1588, 1584, 1570, 1549 and 1496 cm À1 for DFT are observed to be within a good range with experimental data. All the stretching C@C vibrations are found in the expected range and comparable with the previously related literatures46474849. Meanwhile, the in-plane and out-of-plane C@C bending modes for the naphthalene ring are observed at 990, 906 and 815 cm À1 . "
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