Berlin 2012 – wissenschaftliches Programm
MA 19: Joint Session "Multiferroics III - Strain / New Routes towards Multiferroicity" (jointly with DF, DS, KR, TT)
MA 19.10: Vortrag
Dienstag, 27. März 2012, 12:00–12:15, EB 301
Full-potential DFT+U study of orbitally ordered systems: the importance of non-spherical contributions and double counting — •Adam Jakobsson1,2, Biplab Sanyal1, Ivetta Slipukhina2, Marjana Ležaic2, Ersoy Sasioglu2, Gustav Bihlmayer2, and Stefan Blügel2 — 1Department of Physics and Astronomy, Uppsala University, 75120 Uppsala, Sweden — 2Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
DFT+U has for many years been a standard method to calculate properties of strongly correlated systems. Initially the method  was implemented in DFT-codes using the atomic sphere approximation (ASA) but was later also implemented into full potential DFT-codes. Various flavours of the double counting corrections used in the DFT+U method further add to the variety of different DFT+U functionals. The double counting corrections originally derived in the context of ASA are now routinely applied in full potential codes. Using the FLEUR code , we have investigated the importance of the non-spherical potential and the issue of double counting for orbital ordering and magnetism, i.e. properties that play a crucial role in many multiferroic materials. A recent implementation  of the constrained-RPA method was used to obtain parameters for the DFT+U calculations. This work was supported by the Young Investigators Group Program of the Helmholtz Association, Germany, contract VH-NG-409.
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