ON THE SYNTHESIS AND CRYSTAL-STRUCTURE OF BA6LU4ZN10O22 WITH [OBA6] OCTAHEDRA

Single crystals of Ba6Lu4Zn10O22 have been prepared by high temperatur e reactions and investigated by X-ray techniques. This compound is iso typic to Ba3In2Zn5O11 and the first member of the Rare Earth elements. Ba6Lu4Zn10O22 crystallizes with cubic symmetry, space group T-d(2)-F (4) over bar 3m, a = 13.452(1) Angstrom and Z = 4. Zn2+ shows a tetrah edral, Lu3+ an octahedral and Ba2+ a three-fold capped trigonal prisma tic coordination by O2-. The ZnO4 tetrahedra and LuO6 octahedra are fo rming macro polyhedra of the type Zn10O20 and Lu4O16. A discussion is given for the Ba6O33 and Ba6O42 groups.