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.