Nonstoichiometric Fluorites as Examples of Nanostructured Materials

Other cations of the supercluster, and 2R +, are located in neighbouring layers. 

Microordering areas are about 10-100 nm long. It is impossible to detect these randomly oriented nanometric areas by means of classical XRD because both the fluorite matrix and ordered inclusions have an almost identical cationic sublattice. Slight cation displacements 

The model deals with large isomorphous stmcture blocks of different cationic compositions but not with separate isomorphous ions. The maximum size difference of superclusters is 5.4% (for fluorite matrix [Bai4Fe4] and RE superclusters [BagjLufiFsg ]). It leads to the removal of dimensional restrictions between and 

Separate superclusters group together and form micro-ordering areas (nanoparticles) retaining the fluorite cationic motive of the stmcture. The sizes of such areas are different ranging from several nanometers up to few microns. 

The described model supposes that the micro-ordered areas can correspond even to hypothetical or metastable ordered phases, which are absent on the equilibrium phase diagram. For example, in the process of research of nonstoichiometric 

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