Cubic and tetragonally distorted lithium manganese oxide spinels (LiMnO2+x) were obtained by progressive oxidation of LiMnO2 between 300 and 400°C. Orthorhombic LiMnO2 was prepared by hydrothermal treatment of either γ-MnOOH or Mn(COOCH3)3 · 2H2O with LiOH · H2O in large excess. The reversible specific capacity for LiMnO2+x was found to be sensitive to average manganese valency changeable by the oxidizing condition. The LiMnO2+x exhibits the ferromagnetic behavior with Tc = 20-40 K and the occurrence of spontaneous magnetic moment is associated with the decrease in the development of ferromagnetic interaction accompanying the decrease in the average shortest Mn-Mn distance between Mn ions on octahedral 16d sites.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics