6 NEW BI(V) MATERIALS - LISR3BIO6, NASR3BIO6, NABA3BIO6, LI6KBIO6, LI6RBBIO6, AND LI2BA5BI2O11

Large single crystals of LiSr3BiO6, NaSr3BiO6, NaBa3BiO6, Li6KBiO6, Li6RbBiO6, and Li2Ba5Bi2O11 were grown by precipitation from molten mixtures of alkali and/or alkaline earth metal hydroxides at 550°C. Single crystal X-ray methods were used to solve the structures of NaBa3BiO6, Li6KBiO6, and Li2Ba5Bi2O11. NaBa3BiO6 has trigonal Laue symmetry with unit cell dimensions a=7.226(1) Å and α=91.79(3)°. The structure was refined in the space group R3c to an R value of 2.7%. NaSr3BiO6 [a =6.930(1) Å, α=92.26(1)°] is isostructural and LiSr3BiO6 [a=6.872(1) Å, b=6.864(2) Å, c=6.872(1) Å, α=92.31(2)°, β=92.27(2)°, γ=92.29(2)°] has a related structure. Li6KBiO6 has trigonal Laue symmetry with unit cell dimensions a=5.428(1) Å and α=101.49(1)°. The structure was refined in the space group R3m and was refined to an R value of 4.6%. Li6RbBiO6 [a=5.464(1) Å, α=101.46(1)] is isostructural. Li2Ba5Bi2O11 has orthorhombic Laue symmetry with unit cell dimensions a =14.593(5) Å, b=5.989(1) Å, and c=14.363(2) Å. The structure was refined in the space group Pnma to an R value of 3.6%. In all six materials the Bi(V) atoms are coordinated by an octahedron of oxygen atoms; the Bi(V)-O bond lengths range from 2.04 to 2.17 Å. These materials are hygroscopic, but are otherwise stable under ambient conditions. © 1992 Academic Press, Inc.