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Electrostatic model of atomic ordering in complex perovskite alloys

L. Bellaiche·David Vanderbilt
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Abstract

We present a simple ionic model which successfully reproduces the various types of compositional long-range order observed in a large class of complex insulating perovskite alloys. The model assumes that the driving mechanism responsible for the ordering is simply the electrostatic interaction between the different ionic species. A possible new explanation for the anomalous long-range order observed in some Pb relaxor alloys, involving the proposed existence of a small amount of Pb^4+ on the B sublattice, is suggested by an analysis of the model.

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L. Bellaiche, David Vanderbilt. 1998-06-23. Electrostatic model of atomic ordering in complex perovskite alloys. https://doi.org/10.1103/physrevlett.81.1318

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