Jahn-Teller distortion and magnetic structure in LaMnO3: A first-principles theoretical study with full structure optimizations

The Jahn-Teller (JT) distortion and the magnetic structure of LaMnO3 were studied with first-principles theoretical calculations based on the projector augmented-wave method in generalized gradient approximation (GGA) and GGA+U. If internal coordinates and lattice constants were optimized, GGA calculations failed to predict the experimental ground state with A-type antiferromagnetic (A-AFM) ordering like in other calculations, while GGA+U calculations reproduced the experimental JT distortion and the A-AFM ground state successfully. It was also shown that a large on-site Coulomb repulsion U-eff on the La 4f states does not affect the results significantly.