Optical and structural investigation of the lanthanum. beta. -alumina phase doped with europium

Journal Article · Fri Oct 01 04:00:00 EDT 1976 · J. Solid State Chem.; (United States)

DOI:https://doi.org/10.1016/0022-4596(76)90168-7· OSTI ID:7125094

Dexpert-Ghys, J; Faucher, M; Caro, P

The lanthanum ..beta..-alumina phase doped with europium was investigated by X-ray diffraction and fluorescence. This nonstoichiometric phase exists over the composition range: 11Al/sub 2/O/sub 3//1La/sub 2/O/sub 3/ to 14Al/sub 2/O/sub 3//1La/sub 2/O/sub 3/. The unit cell is hexagonal with a = 5.560 +- 0.003 A, c = 22.001 +- 0.003 A and belongs to the P6/sub 3//mmc space group. X-ray diffraction patterns do not vary between both boundary compositions, but fluorescence spectra show that the structure of the mirror plane in which the lanthanide ions are located is deeply modified. The atomic structure of the mirror plane is of ''..beta..-type'' (like ..beta..(Na) or ..beta..(Ag)) for the lower alumina contents; it gradually changes to a ''magneto-plumbite type'' for higher alumina contents.

• Research Organization: CNRS, Meudon, France
• OSTI ID: 7125094
• Journal Information: J. Solid State Chem.; (United States), Journal Name: J. Solid State Chem.; (United States) Vol. 19:2; ISSN JSSCB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
ALLOYS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CHALCOGENIDES
CHEMICAL ANALYSIS
COHERENT SCATTERING
DIFFRACTION
EUROPIUM ADDITIONS
EUROPIUM ALLOYS
LANTHANUM COMPOUNDS
LANTHANUM OXIDES
MOLECULAR STRUCTURE
NONDESTRUCTIVE ANALYSIS
OXIDES
OXYGEN COMPOUNDS
PHASE STUDIES
PHASE TRANSFORMATIONS
RARE EARTH ADDITIONS
RARE EARTH ALLOYS
RARE EARTH COMPOUNDS
SCATTERING
STOICHIOMETRY
X-RAY DIFFRACTION
X-RAY EMISSION ANALYSIS
X-RAY FLUORESCENCE ANALYSIS