Structural and ferroelectric transitions in magnetic nickelate PbNiO3

Author(s)
X. F. Hao, A. Stroppa, P. Barone, A. Filippetti, C. Franchini, S. Picozzi
Abstract

Density functional calculations have been tremendously useful in

understanding the microscopic origin of multiferroicity and in

quantifying relevant properties in many multiferroics and

magnetoelectrics. Here, we focus on a relatively new and promising

compound, PbNiO3. The structural, electronic and magnetic properties of its two polymorphs, i.e. the orthorhombic structure with space group Pnma and the rhombohedral LiNbO3-type structure with space group R3c have been studied by using density functional calculations within DFT + U

and hybrid functional schemes. Our data convey an accurate description

of the pressure-induced phase transition from the rhombohedral to

orthorhombic phase at a predicted critical pressure of 5 GPa in

agreement with the measured value of 3 GPa. Both phases show the G-type

antiferromagnetic configuration as a magnetic ground state, but differ

in the spatial anisotropy associated with nearest-neighbor exchange

couplings, which is strongly weakened in the rhombohedral LiNbO3-type phase. The predicted large ferroelectric polarization of the rhombohedral phase (Hao et al 2012 Phys. Rev.

B 014116) has been re-explored and analyzed in detail using partial

density of states, Born effective charge tensors, charge density

difference, electron localization function analysis and distortion mode

analysis. The asymmetric bonding between the Pb 6s and O 2p orbitals

along the [111]-direction is responsible for the polar cationic

displacement, giving rise to a predicted large ferroelectric

polarization as high as  ~ 100 μC cm−2.

Organisation(s)
Computational Materials Physics
External organisation(s)
Technische Universität Wien, Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", CNR, Center for Computational Materials Science, CMS, Università degli Studi di Cagliari
Journal
New Journal of Physics
Volume
16
No. of pages
20
ISSN
1367-2630
DOI
https://doi.org/10.1088/1367-2630/16/1/015030
Publication date
01-2014
Peer reviewed
Yes
Austrian Fields of Science 2012
103009 Solid state physics, 103015 Condensed matter, 103025 Quantum mechanics, 103036 Theoretical physics
Keywords
Portal url
https://ucrisportal.univie.ac.at/en/publications/feeb6d79-80d7-437c-8cfe-6992aed64411