Revisiting the Structural, Electronic, and Magnetic Properties of (LaO)MnAs: Effect of Hubbard Correction and Origin of Mott-Insulating Behavior.

We study the structural, electronic, and magnetic properties of the antiferromagnetic-layered oxyarsenide (LaO)MnAs system from the first-principle calculation. The increasing Hubbard energy () in the Mn 3d orbital induces the increasing local-symmetry distortions (LSDs) in MnAs and OLa tetrahedra. The LSD in MnAs tetrahedra is possibly promoted by the second-order Jahn-Teller effect in the Mn 3d orbital.