Cooperative Jahn-teller Effect on the Magnetic Structure of Manganese Oxides *
نویسندگان
چکیده
The magnetic structure of LaMnO3 is investigated on three-dimensional clusters of MnO6 octahedra by using a combination of relaxation and Monte Carlo techniques. It is found that the cooperative Jahn-Teller phonons lead to the stabilization of A-type antiferromagnetic and C-type orbital structures in the physically relevant region of parameter space for LaMnO3 with small corrections due to tilting effects. The results suggest that strong Coulomb interactions are not necessary for a qualitative description of undoped manganites. In fact, it is shown that the present result is not essentially changed even if the Coulomb interaction is explicitly included.
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