Conduction and disorder in Y(3)NbO(7) - Zr(2)Y(2)O(7)

The construction of interaction potentials for the Y 0.5+0.25xNb0.25xZr0.5-0.5xO1.75 system, on a purely ab-initio basis, is described. These potentials accurately reproduce experimental data on both the structure and the dynamics of these systems; the computer simulations also reproduce the experim...

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Bibliographic Details
Main Authors: Marrocchelli, D, Madden, P, Norberg, S, Hull, S
Format: Journal article
Language:English
Published: 2009
Description
Summary:The construction of interaction potentials for the Y 0.5+0.25xNb0.25xZr0.5-0.5xO1.75 system, on a purely ab-initio basis, is described. These potentials accurately reproduce experimental data on both the structure and the dynamics of these systems; the computer simulations also reproduce the experimental trend of the conductivity, which decreases as x increases, and of the level of static disorder within the O2- sublattice, which increases with x. A detailed analysis of these phenomena shows that the static disorder in Y 3NbO7 is caused by the high Nb5+ charge and that in this material the conduction is heterogeneous, i.e. some anions are completely immobile while some others are very mobile. The role of the cation sublattice is explained in detail.