A crystal-chemical framework for relaxor versus normal ferroelectric behavior in tetragonal tungsten bronzes
Abstract
Tetragonal Tungsten Bronzes (TTBs) - an important class of oxides known to exhibit ferroelectricity - undergo complex distortions, including rotations of oxygen octahedra, which give rise to either incommensurately or commensurately modulated superstructures. Many TTBs display broad, frequency-dependent relaxor dielectric behaviour rather than sharper frequency-independent normal ferroelectric anomalies but the exact reasons that favor a particular type of dielectric response for a given composition remain unclear. In this contribution the influence of incommensurate/commensurate displacive modulations on the onset of relaxor/ferroelectric behaviour in TTBs is assessed in the context of basic crystal-chemical factors, such as positional disorder, ionic radii and polarizabilities, and point defects. We present a predictive crystal-chemical model that rationalizes composition-structure-properties relations for a broad range of TTB systems.
Citation
Zhu , X , Fu , M , Stennett , M C , Vilarinho , P M , Levin , I , Randall , C A , Gardner , J , Morrison , F D & Reaney , I M 2015 , ' A crystal-chemical framework for relaxor versus normal ferroelectric behavior in tetragonal tungsten bronzes ' , Chemistry of Materials , vol. 27 , no. 9 , pp. 3250-3261 . https://doi.org/10.1021/acs.chemmater.5b00072
Publication
Chemistry of Materials
Status
Peer reviewed
ISSN
0897-4756Type
Journal article
Description
Ian M. Reaney acknowledges the support of the National Institute of Standards and Technology Visiting Scientist program.Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.