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Octahedral tilts and electronic correlations in La_7/8Sr_1/8MnO_3

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 نشر من قبل Jochen Geck
 تاريخ النشر 2006
  مجال البحث فيزياء
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We present a resonant x-ray scattering study of the octahedral tilt order between 50K and 310K in La_7/8Sr_1/8MnO_3. At the La L_II-edge the resonant (300) reflection probes cooperative tilts of the MnO_6-octahedra in this material, as verified by a model caclulation as well as a LDA+U study. The investigation of the octahedral tilts as a function of temperature and the comparison to the lattice parameters, the magnetization and the superlattice reflections related to charge and/or orbital order reveal an intimate coupling between electronic and tilt degrees of freedom in La_7/8Sr_1/8MnO_3.



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