New Defect-crystal-chemical approach to non-vegardianity and complex defect structure of fluorite-based MO-LnO solid solutions (M=Ce, Th; Ln= Lanthanide), 2; Detailed local-structure and ionic-conductivity analysis

Nakamura, Akio

Part I proposed a new lattice-parameter (a(ss)) model for Defect-Fluorite (DF) MLnO solid solutions (ss);this clarified their markedly non-Vegardian behavior as a macroscopic manifestation of their microscopic non-randomness represented by non-random CN(Ln, M) data. Part II further clarified that these CN(Ln, M) data can provide a quantitative description of their detailed non-random local structure such as mutually non-randomly defect (V)-coordinated cation concentrations and their intriguing ionic-conductivity behavior as a multiple V - O transport process. Thus, the present model is proposed as a new quantitative a(ss) model for DF oxides and as a new direct link to their controversial defect structure. A complete description of the methodology and results of detailed local-structure and ionic-conductivity analysis is given, mainly focusing on Ce-Y.