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Updated: Jun 10, 2026
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High-Pressure NMR Experiments for Detecting Protein Low-Lying Conformational States
Published on: June 29, 2021
Pressure-induced phase transitions in L-alanine, revisited
N A Tumanov1, E V Boldyreva, B A Kolesov
1Novosibirsk State University, REC-008, Pirogova 2, Novosibirsk 90, Russia.
Acta Crystallographica. Section B, Structural Science
|July 16, 2010
Summary
High pressure studies reveal L-alanine does not undergo structural phase transitions. New solvate phases were observed under pressure, reverting to L-alanine upon decompression.
Area of Science:
- Crystallography
- Materials Science
- Physical Chemistry
Background:
- L-alanine is a fundamental amino acid with potential applications in various fields.
- Understanding its behavior under extreme conditions, such as high pressure, is crucial for exploring new material properties and applications.
Purpose of the Study:
- To investigate the structural response of L-alanine to applied pressure.
- To identify any pressure-induced phase transitions or structural modifications.
- To characterize potential new phases formed under pressure.
Main Methods:
- X-ray powder diffraction (up to 12.3 GPa)
- Single-crystal X-ray diffraction
- Raman spectroscopy
- Optical microscopy (up to ~6 GPa)
Main Results:
- No structural phase transitions were observed in L-alanine up to 12.3 GPa.
- Cell parameters changed continuously, with parameters 'a' and 'b' becoming equal around 2 GPa without symmetry change.
- Two new orthorhombic phases, likely solvates, were crystallized under pressure (0.8-4.7 GPa) and reverted to L-alanine upon decompression.
Conclusions:
- L-alanine remains orthorhombic under high pressure without observed phase transitions.
- The formation of solvate phases suggests complex interactions with the pressure-transmitting medium.
- Observed changes in intermolecular interactions are reflected in Raman spectra.
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