%0 Journal Article
%T Low-temperature Raman spectra of L-histidine crystal
%A G. P. De Sousa
%A P. T. C. Freire
%A J. Mendes Filho
%A F. E. A. Melo
%A C. L. Lima
%J Physics
%D 2013
%I arXiv
%R 10.1007/s13538-013-0132-3
%X We present a Raman spectroscopy investigation of the vibrational properties of L-histidine crystals at low temperatures. The temperature dependence of the spectra show discontinuities at 165 K, which we identify with modifications in the bonds associated to both the NH3+ and CO2- motifs indicative of a conformational phase transition that changes the intermolecular bonds. Additional evidence of such a phase transition was provided by differential scanning calorimetry measurements, which identified an enthalpic anomaly at ~165 K.
%U http://arxiv.org/abs/1304.7692v1