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The Effect of Symmetry Lowering on the Dielectric Response of $BaZrO_3$

Joseph W. Bennett·Ilya Grinberg·Andrew M. Rappe
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Abstract

We use first-principles density functional theory calculations to investigate the dielectric response of BaZrO$_3$ perovskite. A previous study [Arkbarzadeh {\em et al.} Phys. Rev. B {\bf 72}, 205104 (2005)] reported a disagreement between experimental and theoretical low temperature dielectric constant $ε$ for the high symmetry BaZrO$_3$ structure. We show that a fully relaxed 40-atom BaZrO$_3$ structure exhibits O$_6$ octahedral tilting, and $ε$ that agrees with experiment. The change in $ε$ from high-symmetry to low-symmetry structure is due to increased phonon frequencies as well as decreased mode effective charges.

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Joseph W. Bennett, Ilya Grinberg, Andrew M. Rappe. 2006-03-24. The Effect of Symmetry Lowering on the Dielectric Response of $BaZrO_3$. https://doi.org/10.1103/physrevb.73.180102

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