Abstract
Apatite-type rare earth silicates/germanates have attracted considerable interest recently due to their high oxide ion conductivities. Despite evidence in support of a conduction mechanism involving interstitial oxide ions, the exact location of the interstitial oxide ion sites continues to attract controversy. In this paper we report a neutron diffraction structural study for the high oxygen excess compound, La8Y2Ge6O27. The structural model indicates that the oxide ions are located between the GeO4 tetrahedra, leading to significant localised distortions. These results, coupled with recent modelling studies, hence, support the conclusion that oxide ion migration proceeds via these tetrahedra.
Original language | English |
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Pages (from-to) | 7955-7958 |
Number of pages | 4 |
Journal | Journal of Materials Chemistry |
Volume | 19 |
Issue number | 42 |
DOIs | |
Publication status | Published - 9 Sept 2009 |