Importance of correlation effects on magnetic anisotropy in Fe and Ni - art. no. 216405

We calculate magnetic anisotropy energy of Fe and Ni by taking into account the effects of strong electronic correlations, spin-orbit coupling, and no ncollinearity of intra-atomic magnetization. The LDA + U method is used and its equivalence to dynamical mean-field theory in the static limit is emph asized. Both experimental magnitude of magnetic anisotropy energy and direc tion of magnetization are predicted correctly near U = 1. 9 eV, J = 1.2 eV for Ni and U = 1.2 eV, J = 0.8 eV for Fe. Correlations modify the one-elect ron spectra which are now in better agreement with experiments.