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Ab initio Study of Valley Line on a Total-Energy Surface for Zone-Center Distortions of Ferroelectric Perovskite Oxides BaTiO3 and PbTiO3

Takeshi Nishimatsu·Takatoshi Hashimoto·Hiroshi Mizuseki·Yoshiyuki Kawazoe·Atsushi Sasaki·Yoshiaki Ikeda
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Abstract

An ab initio structure optimization technique is newly developed to determine the valley line on a total-energy surface for zone-center distortions of ferroelectric perovskite oxides and is applied to barium titanate BaTiO3 and lead titanate PbTiO3. The proposed technique is an improvement over King-Smith and Vanderbilt's scheme [Phys. Rev. B 49, p.5828 (1994)] of evaluating total energy as a function of the amplitude of atomic displacements. The results of numerical calculations show that total energy can be expressed as a fourth-order function of the amplitude of atomic displacements in BaTiO3 but not in PbTiO3.

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Takeshi Nishimatsu, Takatoshi Hashimoto, Hiroshi Mizuseki, Yoshiyuki Kawazoe, Atsushi Sasaki, Yoshiaki Ikeda. 2004-03-24. Ab initio Study of Valley Line on a Total-Energy Surface for Zone-Center Distortions of Ferroelectric Perovskite Oxides BaTiO3 and PbTiO3. https://doi.org/10.1143/jjap.43.6785

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