The Strain-Driven Pyrochlore to ''Defect Fluorite'' Phase Transition in Rare Earth Sesquioxide Stabilized Cubic Zirconias
The relationship between the ordering characteristic of the pyrochlore structure type and that characteristic of the ''defect fluorite'' structure type (immediately on either side of two phase regions separating the two structure types) in a range of rare earth sesquioxide-stabilized cubic zirconias was investigated by electron diffraction and imaging. Systematic structural change as a function of composition and relative size of the constituent metal ions is highlighted, and a multi-q to single-q = {1/2} [111]* model is proposed for the observed pyrochlore-to-defect fluorite phase transition. Strain introduced into the close-packed {l_brace}111{r_brace} metal ion planes of the defect fluorite average structure by the local cation and oxygen vacancy distribution is pointed to as the likely origin of the observed behavior.
- Research Organization:
- Research School of Chemistry, Australian National University, Canberra, A.C.T. (AU); Centre for Microscopy and Microanalysis, University of Queensland, St. Lucia, Queensland (AU); Departamento de Fisica de la Materia Condensada, Universidad del Pais Vasco, Bilbao (ES)
- Sponsoring Organization:
- None (US)
- OSTI ID:
- 782906
- Journal Information:
- Journal of Solid State Chemistry, Vol. 159, Issue 1; Other Information: PBD: 1 Jun 2001; ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
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