Structure and ionic conductivity of NaCeP2O7

The diphosphate NaCeP2O7 was synthesized and its structure was determined from single crystal X-ray data. The title compound crystallizes in the orthorhombic space group Pnma with: a = 8.6224(4), b = 5.2823(3), c = 12.6796(6) Å, V = 577.51(5) Å3, Z = 4 and R(F2) = 0.0323 for 674 reflections (Fo2 ≥ 2σ(Fo2)) with Rw(F2) = 0.0775, refined with 62 parameters. The structure of NaCeP2O7 consists of P2O74− diphosphate groups which are extended along two perpendicular directions. In the case of the orthorhombic NaCeP2O7, cerium cations are ninefold coordinated and diphosphate groups have a symmetry plane. The sodium cations are coordinated by nine oxygen atoms and build ribbons of NaO9 polyhedra running parallel to the b direction. nductivity of the NaCeP2O7 sample was studied over a temperature range from 293 to 840 K. Transport properties in this material appear to be due to Na+ ionsʹ hopping mechanism.