title: Planar defects and incommensurate phases in highly ordered perovskite solid solutions.
abstract: A first-principles-derived approach is used to study the effects of planar defects on structural properties of a rocksalt-ordered Pb(Sc0.5Nb0.5)O3 alloy. These defects lead to unusual features, including a less symmetrical ground state with respect to the perfectly ordered material. We also propose that a simple and original mechanism, involving these defects, may be responsible for the existence and anomalous characteristics of the incommensurate phases observed in insulating perovskites.
authors.affiliation: Physics Department, University of Arkansas, Fayetteville, Arkansas 72701, USA. ikornev@uark.edu
authors.forename: Igor A
authors.initials: IA
authors.lastname: Kornev
authors.forename: L
authors.initials: L
authors.lastname: Bellaiche