From single-crystal X-ray data, cesium titanium pyrophosphate, CsTiP2O7, is
found to crystallize in the KAlP2O7 structure type. It possesses a three-d
imensional tunnel structure built by the corner-sharing of distorted TiO6 o
ctahedra and P2O7 pyrophosphate groups. The Cs+ cations are in the tunnels.