Magnetism of mixed valence (LaSr) hexaferrites

  • P. Novák
  • K. Knížek
  • M. Küpferling
  • R. Grössinger
  • M. W. Pieper
Solid and Condensed State Physics

Abstract.

The electronic structure of LaxSr1-xFe12O19 (x=0, 0.25, 0.5, 0.75, 1) hexaferrite is calculated using the density functional theory and generalized gradient approximation (GGA). The GGA+U method is used to improve the description of strongly correlated 3d electrons of Fe. The ‘virtual crystal’ approach is employed for the fractional x, its applicability is checked for x=0.5 by comparing it with the supercell method. The electronic charges introduced by the La substitution show no significant preference for any of the iron sublattices. The magnetic moment decreases linearly with the increasing La content in agreement with the experiment.

Keywords

Iron Spectroscopy Neural Network State Physics Complex System 

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Copyright information

© EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2005

Authors and Affiliations

  • P. Novák
    • 1
  • K. Knížek
    • 1
  • M. Küpferling
    • 2
  • R. Grössinger
    • 2
  • M. W. Pieper
    • 2
  1. 1.Institute of Physics of ASCRPrague 6Czech Republic
  2. 2.Institute for Solid State Physics, Technical University ViennaViennaAustria

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