High-pressure properties of TiP2O7, ZrP2O7 and ZrV2O7
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 Z