We investigate the ferrimagnetism and ferroelectricity of bulk NiFe2O4 with tetragonal P4122 ~symmetry by means of density functional calculations using generalized gradient approximation + Hubbard U approach. Special attention is paid to finding the most energetically favorable configuration on magnetic ordering and further calculating the reliable spontaneous electric polarization. With the fully optimized crystalline structure of the most stable configuration, the spontaneous polarization is obtained to be 23 μC/cm2 along the z direction, which originates from the hybridization between the 3d states of the Fe3+ cation and the 2p states of oxygen induced by Jahn-Teller effect.
@article{arxiv.1603.05974,
title = {First-principles study of ferroelectricity induced by p-d hybridization in ferrimagnetic NiFe2O4},
author = {Un-Gi Jong and Chol-Jun Yu and Yong-Su Park and Chong-Suk Ri},
journal= {arXiv preprint arXiv:1603.05974},
year = {2017}
}