Experimental and theoretical study of α–Eu2(MoO4)3 under compression
The compression process in the α-phase of europium trimolybdate was revised employing several experimental techniques. X-ray diffraction (using synchrotron and laboratory radiation sources), Raman scattering and photoluminescence experiments were performed up to a maximum pressure of 21 GPa. In addi...
| Autores: | , , , , , , , , , , , |
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| Formato: | artículo |
| Fecha de publicación: | 2015 |
| País: | España |
| Recursos: | Universitat Politècnica de València (UPV) |
| Repositorio: | RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia |
| Idioma: | inglés |
| OAI Identifier: | oai:riunet.upv.es:10251/84613 |
| Acesso em linha: | https://riunet.upv.es/handle/10251/84613 |
| Access Level: | acceso abierto |
| Palavra-chave: | High pressure X-ray diffraction Raman scaterring Photoluminescence Rare earth trimolybdates α-phase FISICA APLICADA |
| Resumo: | The compression process in the α-phase of europium trimolybdate was revised employing several experimental techniques. X-ray diffraction (using synchrotron and laboratory radiation sources), Raman scattering and photoluminescence experiments were performed up to a maximum pressure of 21 GPa. In addition, the crystal structure and Raman mode frequencies have been studied by means of first-principles density functional based methods. Results suggest that the compression process of α-Eu2(MoO4)3 can be described by three stages. Below 8 GPa, the α-phase suffers an isotropic contraction of the crystal structure. Between 8 and 12 GPa, the compound undergoes an anisotropic compression due to distortion and rotation of the MoO4 tetrahedra. At pressures above 12 GPa, the amorphization process starts without any previous occurrence of a crystalline-crystalline phase transition in the whole range of pressure. This behavior clearly differs from the process of compression and amorphization in trimolybdates with β′-phase and tritungstates with α-phase. |
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