  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.
