Ab initio studies of magnetism in strongly correlated electron systems

We present an ab initio based method which gives clear insight into the int erplay between the band-f hybridization, the band-f coulomb exchange, and t he crystal-field interactions, as the degree of 4f localization is varied a cross a series of strongly correlated cerium systems. The predictions for t he ordered magnetic: moments, magnetic structure, and ordering temperatures are in excellent agreement with experiment, including the occurence of a m oment collapse of non-Kondo origin. In contrast. spin and orbitally polariz ed ah initio density functional calculations and LDA + U calculations fail to predict, even qualitatively, the trend of the unusual magnetic propertie s. (C) 2001 Elsevier Science B.V. All rights reserved.