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Title: Role of A-site and B-site ions in perovskite ferroelectricity

Abstract

The interplay between the various patterns of structural instability that are related to the electromechanical coupling in ferroelectric perovskites is discussed using results of density functional based first principles calculations. We focus on two main issues: (1) the competition between tetragonal and rhombohedral ferroelectric states in A-site driven (tolerance factor, t < 1) perovskites, and (2) the competition of ferroelectricity and antiferroelectric octahedral rotation. The role of Pb is reviewed in terms of cross gap hybridization of Pb 6p states with O 2p orbitals, and an alternate mechanism for reducing the tendency towards tilt instabilities is discussed.

Authors:
 [1];  [2];  [2];  [3]
  1. ORNL
  2. Central Michigan University, Mt. Pleasant
  3. R. J. Mears, LLC, Waltham, MA
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
1003695
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Ferroelectrics; Journal Volume: 338; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; PEROVSKITES; FERROELECTRIC MATERIALS; DENSITY FUNCTIONAL METHOD; ANTIFERROELECTRIC MATERIALS; LEAD; ELECTRONIC STRUCTURE

Citation Formats

Singh, David J, Ghita, M., Fornari, M., and Halilov, S. V. Role of A-site and B-site ions in perovskite ferroelectricity. United States: N. p., 2006. Web. doi:10.1080/00150190600732694.
Singh, David J, Ghita, M., Fornari, M., & Halilov, S. V. Role of A-site and B-site ions in perovskite ferroelectricity. United States. doi:10.1080/00150190600732694.
Singh, David J, Ghita, M., Fornari, M., and Halilov, S. V. Sun . "Role of A-site and B-site ions in perovskite ferroelectricity". United States. doi:10.1080/00150190600732694.
@article{osti_1003695,
title = {Role of A-site and B-site ions in perovskite ferroelectricity},
author = {Singh, David J and Ghita, M. and Fornari, M. and Halilov, S. V.},
abstractNote = {The interplay between the various patterns of structural instability that are related to the electromechanical coupling in ferroelectric perovskites is discussed using results of density functional based first principles calculations. We focus on two main issues: (1) the competition between tetragonal and rhombohedral ferroelectric states in A-site driven (tolerance factor, t < 1) perovskites, and (2) the competition of ferroelectricity and antiferroelectric octahedral rotation. The role of Pb is reviewed in terms of cross gap hybridization of Pb 6p states with O 2p orbitals, and an alternate mechanism for reducing the tendency towards tilt instabilities is discussed.},
doi = {10.1080/00150190600732694},
journal = {Ferroelectrics},
number = 1,
volume = 338,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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