Single-crystal X-ray structure analysis of the low temperature form of LiMn2O4

Crystal structure of the low temperature form of LiMn2O4 has been successfully determined by using single-crystal X-ray diffraction data at 130 K. It belongs to the orthorhombic system, space group Fddd with a=24.750(3) إ, b=24.801(2) إ, c=8.1903(9) إ, and V=5027.4(9) إ3. The structure, including anisotropic displacement parameters for each atom, was refined to the conventional values R1=5.58%, wR2=7.16%, and S=1.180 for 8082 independent reflections. The oxygen sublattice deformation toward the [1 1 0] direction in the low temperature form is clearly observed at 130 K. The structural phase transition around 280 and 320 K was precisely examined by differential scanning calorimetry (DSC) and single-crystal X-ray diffraction measurements using the single-crystal samples.