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Updated: Jul 18, 2025

Synthesis and Microdiffraction at Extreme Pressures and Temperatures
Published on: October 7, 2013
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.
Abstract:
Maleic acid was studied by Raman spectroscopy and powder synchrotron X-ray diffraction (XRD) under high pressure conditions by using a diamond anvil cell. The Raman spectroscopy measurements were performed from ambient pressure up to 9.2 GPa in the 100-3200 cm-1 spectral range. While the XRD measurements were performed up to 10.1 GPa. Here we present the pressure-dependence behavior from both the Raman modes and cell parameters. Maleic acid lattice parameters decrease anisotropically as a function of pressure and a reduction of 27% in the volume of the unit cell was observed. Modifications in the material's compressibility were observed at around 2 and 6 GPa.
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