Abstract: | From single‐crystal X‐ray data, cesium titanium pyrophosphate, CsTiP2O7, is found to crystallize in the KAlP2O7 structure type. It possesses a three‐dimensional tunnel structure built by the corner‐sharing of distorted TiO6 octahedra and P2O7 pyrophosphate groups. The Cs+ cations are in the tunnels. |