1. High pressure Raman spectra of -form of l-glutamic acid
- Author
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Luz-Lima, C., De Sousa, G.P., Lima Jr., J.A., Melo, F.E.A., Mendes Filho, J., Polian, A., Freire, P.T.C., Departamento de Física, Campus Ministro Petrônio Portella Bloco 03, Universidade Federal do Piauí, Universidade Federal do Piauí, Departamento de Física [Fortaleza], Universidade Federal do Ceará = Federal University of Ceará (UFC), Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other] ,Hydrostatic pressure ,Amino acid crystal ,Phase transition - Abstract
International audience; Raman spectroscopy was used to investigate the vibrational properties of l-glutamic acid in the -form in a diamond-anvil cell up to pressures of 21.5 GPa in the spectral region between 20 and 3270 cm−1. From the analysis of the results it was observed that the crystal undergoes an impressive series of phase transitions in this pressure range. The phase transitions are accompanied by modifications in a number of modes and discontinuities in the wavenumber versus pressure plots, as well as by modifications in the bands associated to both rocking and stretching modes of NH3 +. Upon decompression to ambient pressure the original spectra were recovered indicating that the phase transitions are reversible.
- Published
- 2012