High-pressure properties of TiP2O7, ZrP2O7 and ZrV2O7

Summary, in English

High-pressure synchrotron X-ray powder diffraction studies of TiP₂O₇, ZrP₂O₇ and ZrV₂O₇ have been performed. The ZrV₂O₇ structure undergoes a reversible transition at 1.38-1.58 GPa from cubic α- to pseudo-tetragonal β-ZrV₂O₇ that displays an orthorhombic 2 × 3 × 3 supercell. At pressures above 4 GPa, ZrV₂O₇ becomes irreversibly X-ray amorphous. No such transformations are observed for TiP₂O₇ and ZrP₂O₇, which compress smoothly up to the highest investigated pressures (40.3 and 20.5 GPa, respectively). These differences in high-pressure properties are discussed in terms of the negative thermal expansion of ZrV₂O₇. The bulk moduli at ambient pressure (Bo) for TiP₂O₇, ZrP₂O₇, α-ZrV₂O₇ and β-ZrV₂O₇ were estimated to be 42 (3), 39 (1), 17.0 (7) and 20.8 (10) GPa, respectively.

• Author: Stefan Carlson; Anne Marie Krogh Andersen
• Department/s: MAX IV Laboratory
• Publishing year: 2001
• Language: English
• Pages: 7-12
• Publication/Series: Journal of Applied Crystallography
• Volume: 34
• Issue: 1
• Links: http://dx.doi.org/10.1107/S0021889800013856
• Document type: Journal article
• Publisher: International Union of Crystallography
• Status: Published
• ISBN/ISSN/Other: ISSN: 0021-8898