New high-pressure phase and equation of state of Ce2Zr2O8
In this paper we report a new high-pressure rhombohedral phase of Ce2Zr2O8 observed in high-pressure angle-dispersive x-ray diffraction and Raman spectroscopy studies up to nearly 12 GPa. The ambient-pressure cubic phase of Ce2Zr2O8 transforms to a rhombohedral structure beyond 5 GPa with a feeble d...
| Autores: | , , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2012 |
| País: | España |
| Institución: | Universitat Politècnica de València (UPV) |
| Repositorio: | RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia |
| Idioma: | inglés |
| OAI Identifier: | oai:riunet.upv.es:10251/35868 |
| Acceso en línea: | https://riunet.upv.es/handle/10251/35868 |
| Access Level: | acceso abierto |
| Palabra clave: | high pressure Crystal structure x-ray diffraction powders fluorite raman spectra phase transitions Oxidation Equations of state rietveld refinement FISICA APLICADA |
| Sumario: | In this paper we report a new high-pressure rhombohedral phase of Ce2Zr2O8 observed in high-pressure angle-dispersive x-ray diffraction and Raman spectroscopy studies up to nearly 12 GPa. The ambient-pressure cubic phase of Ce2Zr2O8 transforms to a rhombohedral structure beyond 5 GPa with a feeble distortion in the lattice. The pressure evolution of the unit-cell volume showed a change in compressibility above 5 GPa. The unit-cell parameters of the high-pressure rhombohedral phase at 12.1 GPa are a h = 14.6791(3) Å, c h = 17.9421(5) Å, and V = 3348.1(1) Å3. The structure relations between the parent cubic (P213) and rhombohedral (P32) phases were obtained via group-subgroup relations. All the Raman modes of the cubic phase showed linear evolution with pressure, with the hardest one at 197 cm¿1. Some Raman modes of the high-pressure phase have a non-linear evolution with pressure, and softening of one low-frequency mode with pressure is found. The compressibility, equation of state, and pressure coefficients of Raman modes of Ce2Zr2O8 are also reported. © 2012 American Institute of Physics |
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