Electrostatic Model of Atomic Ordering in Complex Perovskite Alloys
نویسندگان
چکیده
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 Pb14 on the B sublattice, is suggested by an analysis of the model. [S0031-9007(98)06793-3]
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