| Autor: |
Garg, Alka B., Rao, Rekha, Sakuntala, T., Wani, B. N., Vijayakumar, V. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; Sep2009, Vol. 106 Issue 6, p063513-063519, 6p, 5 Charts, 8 Graphs |
| Abstrakt: |
The phase stability of YbVO4 under pressure has been investigated using synchrotron based angle dispersive x-ray diffraction and Raman spectroscopic techniques up to 34.5 and 26.5 GPa, respectively. The results indicate that the compound transforms from the ambient pressure zircon structure to the scheelite structure above 5.9 GPa with 11.8% volume discontinuity. The coexistence of the two phases is observed over a large pressure range. At 15.8 GPa, the (011) peak of the scheelite phase develops asymmetry, and the pattern at further high pressures could be fitted to a fergusonite-type monoclinic structure. On reducing the pressure, the fergusonite phase reverses back to the scheelite phase; the latter phase could be recovered as a metastable phase at ambient pressure. The refined structural parameters along with the equation of state are given for various phases of YbVO4. Changes in the vibrational properties across these transitions, particularly across the scheelite↔fergusonite transition, have been investigated using Raman spectroscopy. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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