I. Nagy1,2 and I. Aldazabal2,3 1Department of Theoretical Physics, Institute of Physics, Technical University of Budapest, H-1521 Budapest, Hungary 2Donostia International Physics Center DIPC, P. Manuel de Lardizabal 4, E-20018 San Sebastián, Spain 3Centro de Fı́sica de Materiales (CSIC-UPV/EHU) MPC, P. Manuel de Lardizabal 3, E-20018 San Sebastián, Spain (Received 28 January 2010; published 7 M...