Charge and spin ordering in LiMn2O4 -: art. no. 094422

X-ray diffraction, neutron diffraction, and susceptibility measurements were performed on (LiMn2O4)-Li-7 Powder specimen. The Jahn-Teller lattice distortion induces a phase transition from cubic to orthorhombic structure at T=283.5 K on cooling. A series of well-defined magnetic Bragg peaks appears below T-N=65 K. A complete charge ordering of Mn3+ and Mn4+ ions in the superlattice structure promotes the antiferromagnetic long-range order. The absence of a magnetic diffuse peak indicates that a magnetic frustration is removed from LiMn2O4 at low temperatures. The dynamics of the lithium ions are also discussed on the basis of the Debye-Waller factor.