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P. Novák, K. KnÍzek, M. Küpferling, R. Grössinger, M. Pieper:
"Magnetism of mixed valence (LaSr) hexaferrites";
European Physical Journal B, 43 (2005), S. 509 - 515.

Eur. Phys. J. B 43, 509-515 (2005)
DOI: 10.1140/epjb/e2005-00084-8
Magnetism of mixed valence (LaSr) hexaferrites
P. Novák1, K. Knízek1, M. Küpferling2, R. Grössinger2 and M.W. Pieper2

1 Institute of Physics of ASCR, Cukrovarnická 10, 162 53 Prague 6, Czech Republic
2 Institute for Solid State Physics, Technical University Vienna, Wiedner Hauptstrasse 8-10, 1040 Vienna, Austria

novakp@fzu.cz

(Received 27 August 2004 / Received in final form 18 January 2005 / Published online 30 March 2005 )

Abstract
The electronic structure of La_xSr_1-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.
PACS
75.50.Gg - Ferrimagnetics.
71.28.+d - Narrow band systems, intermediate valence solids.

http://aleph.ub.tuwien.ac.at/F?base=tuw01&func=find-c&ccl_term=AC05937915

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