High – pressure Raman study of L - alanine crystal
نویسنده
چکیده
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 D2 normal phase undergoes a transition. Pressure coefficients for external modes are also given.
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