Oxyfluorides ionic conductivity

Substitution Variants. The fluorite-type structure is maintained in principle when alkaline earth elements are replaced partially by rare-earth elements. Charge compensation is achieved by occupation of additional interstitial anionic sites.The coordination of the metal atoms may increase from 8 to 9 or even 10 by this. Another way of charge balance is the partial replacement of fluorine by oxygen to form oxyfluorides. Since the possible interstitial positions provide pathways for anion disorder and movement, this class of materials shows fluoride ionic conductivity. 

Ravez J. The inorganic fluoride and oxyfluoride faroelectrics. J. Phys. HI 1997 7 1129-1144 Reau J.M., Hagenmuller P. Fast ionic conductivity of fluorine anions with fluorite- or tysonite-type... 

K. T. Jacob, V. S. Saji, Lanthanum Oxyfluoride Structure, Stability and Ionic conductivity, Int. J. Appl. Ceram. TechnoL, 3, 312-321 (2006). 

V. A. Prituzhalov, E. V. Khomyakova, E. I. Ardashnikova, V. A. Dolgikh, Connection between electronic structure of cation and anionic conductivity of the fluorite-type oxyfluorides, 9-th International Meeting Fundamental Problems of Solid State Ionics Chemogolovka, 125 (2008). 

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