Ab initio study of disorder effects on the electronic and magnetic structure of Sr2FeMoO6 - art. no. 064408

We have investigated the electronic structure of ordered and disordered Sr2 FeMoO6 using ab initio bandstructure methods. The effect of disorder was si mulated within supercell calculations to realize several configurations wit h mis-site disorders. It is found that such disorder effects destroy the ha lf-metallic ferromagnetic state of the ordered compound. It also leads to a substantial reduction of the magnetic moments at the Fe sites in the disor dered configurations. Most interestingly, it is found for the disordered co nfigurations that the magnetic coupling within the Fe sublattice as well as that within the Mo sublattice always remain ferromagnetic, while the two s ublattices couple antiferromagnetically, in close analogy to the magnetic s tructure of the ordered compound, but,in contrast to recent suggestions.