Structural stability of lithium manganese oxides

We have studied stability of lithium-manganese oxides using density functional theory in the local density and generalized gradient approximation (GGA). In particular, the effect of spin-polarization and magnetic ordering on the relative stability of various structures is investigated. At all lithium compositions the effect of spin polarization is large, although it does not affect different structures to the same extent. At composition LiMnO₂, globally stable Jahn-Teller distortions could only be obtained in the spin-polarized GGA approximation, and antiferromagnetic spin ordering was critical to reproduce the orthorhombic LiMnO₂ structure as ground state. We also investigate the effect of magnetism on the Li intercalation potential, an important property for rechargeable Li batteries.