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Updated: Jan 1, 2026
High Pressure Single Crystal Diffraction at PX^2
Published on: January 16, 2017
High-pressure studies on l,l-dileucine crystals by Raman spectroscopy and synchrotron X-ray diffraction combined with
C B Silva1, J G da Silva Filho2, G S Pinheiro3
1Departamento de Física, Universidade Federal do Ceará, C.P. 6030, Campus do Pici, 60.455-760 Fortaleza, CE, Brazil.
Abstract:
The vibrational properties of the dipeptide l-leucyl-l-leucine hydrate were investigated through Raman and infrared spectroscopy. With the aid of first principle calculations using the density functional theory, the assignment of the vibrational modes from the material was furnished. In addition, the behavior of the crystal under high pressure was investigated using Raman spectroscopy (~8 GPa) and synchrotron X-ray diffraction (~26 GPa). The results show significant changes in both the X-ray diffractogram and the Raman spectra, suggesting that l-leucyl-l-leucine hydrate undergoes a phase transition between 2.3 and 2.9 GPa. Finally, for pressures above 16 GPa the broadening of X-ray peaks suggests a disorder in the crystal lattice induced by high-pressure effects.
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