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arXiv · 1304.7692

Low-temperature Raman spectra of L-histidine crystal

G. P. De Sousa·P. T. C. Freire·J. Mendes Filho·F. E. A. Melo·C. L. Lima
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Abstract

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.

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G. P. De Sousa, P. T. C. Freire, J. Mendes Filho, F. E. A. Melo, C. L. Lima. 2013-04-26. Low-temperature Raman spectra of L-histidine crystal. https://doi.org/10.1007/s13538-013-0132-3

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