Crystal and magnetic structure of cesium superoxide

Cesium superoxide is magnetic, due to the half-occupied $\ensuremath{\pi}$ orbitals on its O${}_{2}^{\ensuremath{-}}$ molecules. Neutron diffraction experiments done here find that the crystal structure undergoes a sequence of transitions from tetragonal to incommensurate to orthorhombic, with the latter two exhibiting staggered displacements of the cesium ions. The symmetry of this structure permits antisymmetric exchange, which is consistent with a canted antiferromagnetic structure also observed, and a nice example of a structure-property relationship.