Annihilation of antiferromagnetic order in LiCoO&lt;sub&gt;2&lt;/sub&gt; by excess Li

Sugiyama, Jun; Ikedo, Yutaka; Nozaki, Hiroshi; Mukai, Kazuhiko; Andreica, Daniel; Amato, Alex; Ménétrier, Michel; Carlier, Dany; Delmas, Claude

doi:10.1016/j.physb.2008.11.177

Annihilation of antiferromagnetic order in LiCoO₂ by excess Li

Sugiyama J, Ikedo Y, Nozaki H, Mukai K, Andreica D, Amato A, Ménétrier M, Carlier D & Delmas C

Citation

Sugiyama, J., Ikedo, Y., Nozaki, H., Mukai, K., Andreica, D., Amato, A., … Delmas, C. (2009). Annihilation of antiferromagnetic order in LiCoO₂ by excess Li. Physica B: Condensed Matter, 404(5-7), 769-772. https://doi.org/10.1016/j.physb.2008.11.177

Persistent URL https://www.dora.lib4ri.ch/psi/islandora/object/psi:17313

In order to elucidate the origin of antiferromagnetic (AF) order below 30 K in LiCoO₂, in which all the Co³⁺ ions are in a low-spin state with S = 0, the magnetic nature of the Li-excess sample Li_1.04Co_0.96O_1.96 was studied by muon-spin spectroscopy in the temperature range between 1.8 and 100 K. Although disordered localized moments appeared below 25 K, static AF order was not detected even at 1.8 K. Moreover, a small amount of excess Li ions (4%) and oxygen vacancies (2%) was found to change ∼50% of the sample into a magnetically disordered phase at 1.8 K. The stoichiometric LiCoO₂, which was prepared from the same starting materials to those for the Li-excess sample, showed an AF transition at 30 K, while the volume fraction of the AF phase was 10% even at 1.8 K. This therefore excludes the possible role of the excess Li⁺ on the formation of static AF order.