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arXiv · 1108.2915

Polar octahedral rotations: a path to new multifunctional materials

Nicole A. Benedek·Andrew T. Mulder·Craig J. Fennie
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Abstract

Perovskite ABO$_3$ oxides display an amazing variety of phenomena that can be altered by subtle changes in the chemistry and internal structure, making them a favorite class of materials to explore the rational design of novel properties. Here we highlight a recent advance in which rotations of the BO$_6$ octahedra give rise to a novel form of ferroelectricity -- hybrid improper ferroelectricity. Octahedral rotations also strongly influence other structural, magnetic, orbital, and electronic degrees of freedom in perovskites and related materials. Octahedral rotation-driven ferroelectricity consequently has the potential to robustly control emergent phenomena with an applied electric field. The concept of `functional' octahedral rotations is introduced and the challenges for materials chemistry and the possibilities for new rotation-driven phenomena in multifunctional materials are explored.

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Nicole A. Benedek, Andrew T. Mulder, Craig J. Fennie. 2011-08-15. Polar octahedral rotations: a path to new multifunctional materials. https://doi.org/10.1016/j.jssc.2012.04.012

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