Orbital ordering in paramagnetic LaMnO3 and KCuF3
نویسندگان
چکیده
Ab initio studies of the stability of orbital ordering, its coupling to magnetic structure and its possible origins ~electron-phonon and/or electron-electron interactions! are reported for two perovskite systems, LaMnO3 and KCuF3. We present an average spin state calculational scheme that allowed us to treat a paramagnetic state and to succesfully describe the experimental magnetic or orbital phase diagram of both LaMnO3 and KCuF3 in crystal structures when the Jahn-Teller distortions are neglected. Hence, we conclude that the orbital ordering in both compounds is purely electronic in origin.
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