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Updated: Jul 18, 2025
07:26
Synthesis and Microdiffraction at Extreme Pressures and Temperatures
Published on: October 7, 2013
11.2K
In situ Raman spectroscopy and synchrotron X-ray diffraction studies on maleic acid under high pressure conditions
F M Rufino1, D L M Vasconcelos2, P T C Freire1
1Departamento de Física, Universidade Federal do Ceará, C. P. 6030, CEP 60455-900 Fortaleza, CE, Brazil.
Summary
High pressure studies reveal maleic acid
Area of Science:
- Solid-state chemistry
- Materials science under extreme conditions
Background:
- Understanding the behavior of organic molecules under high pressure is crucial for various scientific fields.
- Maleic acid is a fundamental organic compound with applications in polymer and pharmaceutical industries.
Purpose of the Study:
- To investigate the structural and vibrational changes of maleic acid under high pressure.
- To determine the compressibility and anisotropic behavior of maleic acid.
Main Methods:
- High-pressure Raman spectroscopy up to 9.2 GPa.
- Powder synchrotron X-ray diffraction (XRD) up to 10.1 GPa.
- Utilized a diamond anvil cell for pressure generation.
Main Results:
- Anisotropic decrease in maleic acid lattice parameters with increasing pressure.
- Observed a significant 27% reduction in unit cell volume.
- Identified modifications in compressibility around 2 GPa and 6 GPa.
Conclusions:
- Maleic acid exhibits significant structural changes and anisotropic compression under high pressure.
- The observed compressibility modifications suggest pressure-induced phase transitions or significant changes in bonding.
- Raman spectroscopy and XRD are effective tools for probing molecular behavior under extreme conditions.
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