Polymorphism of the Rare Earth Digermanates and Disilicates Under High Pressure and Information Given by the Eu3+ Structural Probe

  • G. Bocquillon
  • C. Chateau
  • J. Loriers


The structural relationships between the compounds of general formula M2A2O7 have been the subject of numerous investigations. In particular, Brown (1) and Shannon (2) have shown that the crystalline structure of these compounds depends mainly on the respective volumes of the cations M and A: most of the compounds having a relatively large A cation (ionic radius >0.60 Å) crystallize in the pyrochlore structure, whereas the others (phosphates,silicates and germanates) exhibit a large variety of structure types, with frequent analogies between the series.


Rare Earth Boron Nitride Electric Dipole Transition Pyrochlore Phase Gold Foil 
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Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • G. Bocquillon
    • 1
  • C. Chateau
    • 1
  • J. Loriers
    • 1
  1. 1.Centre National De La Recherche ScientifiqueLaboratoires De BellevueMeudonFrance

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