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Pressure-induced metal-insulator transition in LaMnO3 is not of Mott-Hubbard type

A. Yamasaki·M. Feldbacher·Y. -F. Yang·O. K. Andersen·K. Held
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Abstract

Calculations employing the local density approximation combined with static and dynamical mean-field theories (LDA+U and LDA+DMFT) indicate that the metal-insulator transition observed at 32 GPa in paramagnetic LaMnO3 at room temperature is not a Mott-Hubbard transition, but is caused by orbital splitting of the majority-spin eg bands. For LaMnO3 to be insulating at pressures below 32 GPa, both on-site Coulomb repulsion and Jahn-Teller distortion are needed.

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A. Yamasaki, M. Feldbacher, Y. -F. Yang, O. K. Andersen, K. Held. 2006-05-02. Pressure-induced metal-insulator transition in LaMnO3 is not of Mott-Hubbard type. https://doi.org/10.1103/physrevlett.96.166401

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