Raman spectroscopic study of DL valine under pressure up to 20 GPa
Résumé
DL-valine crystal was studied by Raman spectroscopy under hydrostatic pressure using a diamond anvil
cell from ambient pressure up to 19.4 GPa in the spectral range from 40 to 3300 cm1. Modifications in
the spectra furnished evidence of the occurrence of two structural phase transitions undergone by this
racemic amino acid crystal. The classification of the vibrational modes, the behavior of their wavenumber
as a function of the pressure and the reversibility of the phase transitions are discussed.