CRYSTAL-STRUCTURE OF RBZN PO4

Single crystals of RbZnPO4 were grown in rubidium molybdate flux. X-ray crystallography has shown that the title compound crystallizes in the monoclinic system with space group P2(1) and the parameters a = 8.855(3) angstrom, b = 5.408(1) angstrom, c = 8.956(4) angstrom, beta = 90.90(3)-degrees,Z = 4. The structure was solved from 2093 independent reflections with R = 0.045 (Rw = 0.061). The crystal lattice can be described as a three dimensional network of PO4 and ZnO4 tetrahedra linked by one oxygen and developing large cavities where Rb+ cations are located. RbZnPO4 undergoes two phase transitions at 480 and 870-degrees-C. The former has been considered as ferroelastic as in CsZnPO4.