STUDY OF THE MOLECULAR STRUCTURE OF VALINE BY QUANTUMCHEMICAL CALCULATIONS

Abstract

In this paper, calculations were performed in an isolated system using ab initio and Density Functional Theory (DFT) approaches to investigate the mechanism of molecular complex formation in valine, an amino acid. Calculations have represented that the valine molecule has intramolecular hydrogen bonds and that intermolecular hydrogen bonds are used to generate dimer and trimer complexes. The Raman spectral line (?? (OH) = 3749 cm−1 ) corresponding to the O-H vibration of the valine molecule shifted to a lower frequency of 343.9 cm-1 at the O-H bond in the trimer complex and 1533.2 cm-1 at the O-H bond due to intermolecular hydrogen bonding