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arXiv · 1105.0272

Zircon to monazite phase transition in CeVO4

V. Panchal·S. Lopez-Moreno·D. Santamaria-Perez·D. Errandonea·F. J. Manjon·P. Rodriguez-Hernandez·A. Munoz·S. N. Achary·A. K. Tyagi
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Abstract

X-ray diffraction and Raman-scattering measurements on cerium vanadate have been performed up to 12 and 16 GPa, respectively. Experiments reveal that at 5.3 GPa the onset of a pressure-induced irreversible phase transition from the zircon to the monazite structure. Beyond this pressure, diffraction peaks and Raman-active modes of the monazite phase are measured. The zircon to monazite transition in CeVO4 is distinctive among the other rare-earth orthovanadates. We also observed softening of external translational Eg and internal B2g bending modes. We attributed it to mechanical instabilities of zircon phase against the pressure-induced distortion. We additionally report lattice-dynamical and total-energy calculations which are in agreement with the experimental results. Finally, the effect of non-hydrostatic stresses on the structural sequence is studied and the equations of state of different phases are reported.

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V. Panchal, S. Lopez-Moreno, D. Santamaria-Perez, D. Errandonea, F. J. Manjon, P. Rodriguez-Hernandez, A. Munoz, S. N. Achary, A. K. Tyagi. 2011-05-02. Zircon to monazite phase transition in CeVO4. https://doi.org/10.1103/physrevb.84.024111

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