Local spin density approximation calculations are used to elucidate the electronic and magnetic properties of layered ${\mathrm{LiMnO}}_2$ . An insulating ground state with magnetic high spin Mn is found, consistent with the distortion of the O octahedra. However, there is Mn 3d–O 2p hybridization, which reduces the spin moment considerably from the nominal Hund's rule value. The magnetic coupling within the ${\mathrm{MnO}}_2$ trilayers is antiferromagnetic and frustrated, while the coupling between trilayers is very weak. This may result in a suppression of long range order down to low temperatures despite the strong intralayer magnetic interactions and resulting magnetic correlations. The results imply that these will be largely one dimensional along the b-axis Mn chains.

• Received 11 July 1996

DOI:https://doi.org/10.1103/PhysRevB.55.309