Synthese und Kristallstruktur von Pb₂LnAl₃O₈ (Ln = Eu, Gd) / Synthesis and Crystal Structure of Pb₂LnAl₃O₈ (Ln = Eu, Gd)

Abstract

Single Crystals of Pb2LnAl30 8 (Ln = Eu, Gd) have been prepared_by flux techniques. The compounds crystallize with cubic symmetry, space group Oh-Pn3m, fl(Eu) = 9.4578(5), fl(Gd) = 9.4448(7) A, Z = 4. The crystal structure is characterized by heterocubane units of the type Pb40 4 and hexagonal bipyramids of oxygen around the rare earth ions. These com ponents form a network made of macro polyhedra of the type Pb404-L n 0 6-P b 404.