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

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 نشر من قبل Atsushi Yamasaki
 تاريخ النشر 2006
  مجال البحث فيزياء
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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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