AgCe(PO3)4: Synthesis, crystalline structure and ionic conductivity

Single crystals of a new phosphate AgCe(PO3)4 have been prepared by the flux method and its structural and physical properties have been investigated. This compound crystallizes in the monoclinic system with the space group P21/c and its parameters are: a=7.314(1) Å, b=13.239(1) Å, c=12.401(1) Å, β=125.69(1)°, V=975.29(2) Å3 and Z=4. The crystal structure was solved from 3160 X-ray independent reflections with final R(F2)=0.037 and Rw(F2)=0.105 refined with 164 parameters (F02 >4σ(F02). The structure of AgCe(PO3)4 consists of CeO8 polyhedra sharing oxygen atoms with phosphoric group PO4 to form a three-dimensional framework. This type of organization gives rise to a three-dimensional framework. Cerium atoms have an eight-fold coordination while silver atoms have approximately six oxygen neighbours.The conductivity as well as the vibrational study of the cerium phosphate were analyzed in order to explain the mechanism of conduction. Activation energies of 0.57 eV, deduced from the Arrhenius relation.

Complex impedance diagram for AgCe(PO3)4 at 585 K, 555 K and 525 K.Figure optionsDownload as PowerPoint slideHighlights
► Synthesis of a silver cerium polyphosphate.
► Characterization by X-ray diffraction, elemental analyses, IR spectroscopie of the compound.
► Electrical conductivity of AgCe(PO3)4.