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Magnetism of correlated systems: beyond LDA

87   0   0.0 ( 0 )
 نشر من قبل A. Lichtenstein
 تاريخ النشر 2001
  مجال البحث فيزياء
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A novel approach to electronic correlations in magnetic crystals which takes into account a dynamical many-body effects is present. In order to to find a frequency dependence of the electron self energy, an effective quantum-impurity many-particle problem need to be solved within the dynamical mean-field theory. The numerically exact QMC-scheme and the spin-polarized fluctuation exchange approximation are used for the self-consistent solution of this single-site many-particle problem. The calculations of effective exchange interaction parameters based on the realistic electronic structure of correlated magnetic crystals have been discussed.

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