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High-pressure Raman study of L-alanine crystal

A. M. R. Teixeira·P. T. C. Freire·A. J. D. Moreno·J. M. Sasaki·A. P. Ayala·J. Mendes Filho·F. E. A. Melo
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Abstract

Pressure-dependent Raman scattering studies in the range 0.0 -- 32 kbar were carried out in L-alanine in order to investigate its external mode phonon spectra in relation to the phase transitions in the crystal. A careful analysis of the spectra shows that the low-energy Raman modes exhibit variation both in frequency and in intensity and between 26 and 28 kbar it is observed a splitting of a external mode, indicating that the D_2 normal phase undergoes a transition. Pressure coefficients for external modes are also given.

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A. M. R. Teixeira, P. T. C. Freire, A. J. D. Moreno, J. M. Sasaki, A. P. Ayala, J. Mendes Filho, F. E. A. Melo. 2000-01-14. High-pressure Raman study of L-alanine crystal. https://doi.org/10.1016/s0038-1098(00)00342-2

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