Zur Kenntnis eines Barium-Lanthanoid-Aluminat-Zinkats: BaLuAlZn3O7 mit einem Anhang zu Ba2Er2Zn8O13/On a Barium Rare Earth Aluminate Zincate: BaLuAlZn3O7 with a Note on Ba2Er2Zn8O13

Abstract

Abstract Reactions of BaCO3, ZnO, Lu2O3 and Al2O3 mixtures at temperatures up to 1500 °C led to small and colourless rods of BaLuAlZn3O7. The new compound crystallizes with hexagonal symmetry, space group C6v 4 -P63mc, a = 6.273, c =10.161 Å, Z = 2. In spite of small differences in the oxygen content BaLuAlZn3O7 is isotypic to Ba2Ln2Zn8O13. The crystal structure shows Zn2+ with tetrahedral, Lu3+ with octahedral and Ba2+ with anticuboctahedral coordination by O2-. It has been shown that parts of the [Zn3AlO7]5- network are fragments of the ZnO structure. In consequence one oxygen atom is fourfold coordinated by zinc/aluminium. The space group of Ba2Ln2Zn8O13 must be corrected to C6v 4 -P63mc.