Force field calculation of GABA using ab-initio methods and Raman spectroscopy

In this paper, we study in a theoretical way the γ-Aminobutyric acid GABA, which has many important biological functions. The optimized molecular structure was studied by the DFT/B3LYP method with a 6-31 G (d, p) basis set, we used the software Gaussian 09. we are considering the vibrational spectra of the molecule. The Raman spectrum of GABA was recorded in the 4000-40 cm -1 region. This spectrum constitutes the experimental support that allows the theoretical reproduction of the vibrational frequencies. Good agreements were obtained between the observed and calculated frequencies. The scale factors are adjusted to obtain a good agreement between the calculated and observed frequencies. The results obtained reproduce the experimental frequencies.