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Spin and charge ordering in self-doped Mott insulators

T. Mizokawa·D. I. Khomskii·G. A. Sawatzky
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Abstract

We have investigated possible spin and charge ordered states in 3d transition-metal oxides with small or negative charge-transfer energy, which can be regarded as self-doped Mott insulators, using Hartree-Fock calculations on d-p-type lattice models. It was found that an antiferromagnetic state with charge ordering in oxygen 2p orbitals is favored for relatively large charge-transfer energy and may be relevant for PrNiO$_3$ and NdNiO$_3$. On the other hand, an antiferromagnetic state with charge ordering in transition-metal 3$d$ orbitals tends to be stable for highly negative charge-transfer energy and can be stabilized by the breathing-type lattice distortion; this is probably realized in YNiO$_3$.

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T. Mizokawa, D. I. Khomskii, G. A. Sawatzky. 1999-08-02. Spin and charge ordering in self-doped Mott insulators. https://doi.org/10.1103/physrevb.61.11263

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