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Thermodynamic and Structural Evidence for the Presence of Defect Clusters in Some Non-Stoichiometric Oxides

  • O. Toft Sørensen
Part of the NATO ASI Series book series (ASIC, volume 276)

Abstract

Based on thermodynamic data for CeO2-x it is first shown that the non-stoichiometric phase range for this oxide can be devided into subphase regions bounded by intermediate phases with compositions following the general formula MnO2n-2. The defect structure of these phases is then derived using a systematic packing of the basic tetrahedral defect \({\left[ {V_o^{ \bullet \bullet } \cdot 2C{{e'}_{Ce}}} \right]^X}\) and it is shown that lattice parameters determined by X-ray diffraction are well reproduced by the defect structures obtained in this way. Furthermore evidence from statistical thermodynamic calculations and from structural studies (X-ray and neutron scattering) for the existence of these tetrahedral defects in non-stoichiometric fluorite oxides are presented.

Keywords

Oxygen Vacancy Defect Structure Defect Complex Defect Cluster Vacancy Pair 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • O. Toft Sørensen
    • 1
  1. 1.Risø National LaboratoryDenmark

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