MAGNETISM OF UT2SI2 COMPOUNDS - EFFECT OF THE ORBITAL POLARIZATION CORRECTION

Two different ways to deal with correlations in localized f-electron s ystems in the framework of local spin density functional theory are co mpared, using new calculations for the series of uranium intermetallic compounds UT2Si2 (T=Cr,Mn,Fe,Co,Ni,Cu,Ru,Rh,Pd,Os), The strong locali zation and hence atomic like behaviour of the Uranium 5f band states i s taken into account by incorporation of Hund's second rule through an orbital polarization correction (OPC) held. The two OPC methods teste d are the L-2 method and the Orbital Hartree Fock method. Results for electronic and magnetic ground-state properties are compared with prev ious band structure calculations accounting for spin-orbit coupling on ly, as well as with experimental data. Both methods are found to yield a considerable improvement of the theoretical value of the magnetic m oments over standard spinpolarized relativistic density functional cal culations. Furthermore, other aspects such as the impact of the OPC me thods on the calculated density of states are discussed. (C) 1998 Else vier Science Ltd. All rights reserved.