A-type antiferromagnetic and C-type orbital-ordered states in ${\mathrm{LaMnO}}_3$ using cooperative Jahn-Teller phonons

The effect of Jahn-Teller phonons on the magnetic and orbital structure of ${\mathrm{LaMnO}}_3$ is investigated using a combination of relaxation and Monte Carlo techniques on three-dimensional clusters of ${\mathrm{MnO}}_6$ octahedra. In the physically relevant region of parameter space for ${\mathrm{LaMnO}}_3,$ and after including small corrections due to tilting effects, the A-type antiferromagnetic and C-type orbital structures were stabilized, in agreement with experiments.