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arXiv · 0906.4467

Post-Cotunnite phase of TeO2

Gareth I. G. Griffiths·Chris J. Pickard·R. J. Needs
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Abstract

We have used first-principles density-functional-theory methods with a random-structure-searching technique to determine the structure of the previously unidentified post-cotunnite phase of TeO2. Our calculations indicate a transition from the cotunnite to post-cotunnite phase at 130 GPa. The predicted post-cotunnite structure has P2_1/m space group symmetry and its calculated x-ray diffraction pattern is in good agreement with the available experimental data. We find that the cotunnite phase re-enters at about 260 GPa.

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Gareth I. G. Griffiths, Chris J. Pickard, R. J. Needs. 2009-06-24. Post-Cotunnite phase of TeO2. https://doi.org/10.1103/physrevb.80.184115

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