A TiP2O7 superstructure

A room-temperature structural model of titanium pyrophos­phate, TiP₂O₇, has been determined from synchrotron X-ray data. The structure consists of TiO₆ octahedra and PO₄ tetrahedra sharing corners in a three-dimensional network. The PO₄ tetrahedra form P₂O₇ groups connecting the TiO₆ octahedra. The 3 × 3 × 3 superstructure differs substantially from the parent AB₂O₇ structure. The P—O—P bonding angles of the pyrophosphate group are between 141.21 (12) and 144.51 (13)° for those groups not located on the threefold axis. The individual TiO₆ octahedra and PO₄ tetrahedra are somewhat distorted.