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arXiv · 1008.4675

New high-pressure phase of HfTiO4 and ZrTiO4 ceramics

Daniel Errandonea·David Santamaria-Perez·Tatiana Bondarenko·Oleg Khyzhun
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Abstract

We studied the high-pressure effects on the crystalline structure of monoclinic HfTiO4 and ZrTiO4. We found that the compressibility of these ceramics is highly non-isotropic, being the b-axis the most compressible one. In addition, the a-axis is found to have a small and negative compressibility. At 2.7 GPa (10.7 GPa) we discovered the onset of an structural phase transition in HfTiO4 (ZrTiO4), coexisting the low- and high-pressure phases in a broad pressure range. The new high-pressure phase has a monoclinic structure which involves an increase in the Ti-O coordination and a collapse of the cell volume. The equation of state for the low-pressure phase is also determined.

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Daniel Errandonea, David Santamaria-Perez, Tatiana Bondarenko, Oleg Khyzhun. 2010-08-27. New high-pressure phase of HfTiO4 and ZrTiO4 ceramics. https://doi.org/10.1016/j.materresbull.2010.06.061

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