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arXiv · 1206.2761

Exceptionally large room-temperature ferroelectric polarization in the novel PbNiO3 multiferroic oxide

X. F. Hao·A. Stroppa·S. Picozzi·A. Filippetti·C. Franchini
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Abstract

We present a study based on several advanced First-Principles methods, of the recently synthesized PbNiO3 [J. Am. Chem. Soc 133, 16920 (2011)], a rhombohedral antiferromagnetic insulator which crystallizes in the highly distorted R3c crystal structure. We find this compound electrically polarized, with a very large electric polarization of about 100 (\muC/cm)^2, thus even exceeding the polarization of well-known BiFeO3. PbNiO3 is a proper ferroelectric, with polarization driven by large Pb-O polar displacements along the [111] direction. Contrarily to naive expectations, a definite ionic charge of 4+ for Pb ion can not be assigned, and in fact the large Pb 6s-O 2p hybridization drives the ferroelectric distortion through a lone-pair mechanism similar to that of other Pb- and Bi-based multiferroics

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X. F. Hao, A. Stroppa, S. Picozzi, A. Filippetti, C. Franchini. 2012-06-13. Exceptionally large room-temperature ferroelectric polarization in the novel PbNiO3 multiferroic oxide. https://doi.org/10.1103/physrevb.86.014116

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