Thermal stability and crystal structure of β-Ba 3YB 3O 9
Abstract
A new compound, β-Ba 3YB 3O 9, has been attained through solid phase transition from α-Ba 3YB 3O 9 at high temperatures. Differential thermal analysis (DTA) revealed the phase transition at about 1120°C, the melting temperature at about 1253°C. Its crystal structure has been determined from powder X-ray diffraction data. The refinement was carried out using the Rietveld method and the final refinement converged with Rp=10.5% and Rwp=13.7%. This compound belongs to the hexagonal space group R-3, with lattice parameters a=13.0441(1) Å and c=9.5291(1) Å. There are 6 formulas per unit cell and 7 atoms in the asymmetric unit. The structure of β-Ba 3YB 3O 9 is built up from Ba(Y)O 8, BaO 6 and YB 6O 18 units formed by one YO 6 octahedron and six BO 3 triangles with shared O atoms.
- Publication:
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Journal of Solid State Chemistry France
- Pub Date:
- January 2004
- DOI:
- 10.1016/S0022-4596(03)00415-8
- Bibcode:
- 2004JSSCh.177..216L