Spin-dimer ground state driven by consecutive charge and orbital ordering transitions in the anionic mixed-valence compound Rb4O6
A new paper by T. Knaflič, P. Jeglič, M. Komelj, A. Zorko, P. K. Biswas, A. N. Ponomaryov, S. A. Zvyagin, M. Reehuis, A. Hoser, M. Geiß, J. Janek, P. Adler, C. Felser, M. Jansen, and D. Arčon has been published as an Editor’s suggestion in Physical Review B.
“A comprehensive study of the molecular mixed-valence compound Rb4O6 led the authors to the discovery of a peculiar π* orbital ordering transition of magnetic O2− anions within the charge ordered state, which promotes the formation of an orbital order-driven quantum spin state, composed of spin dimers. The experiments suggest that a delicate interplay between an electron-lattice coupling and Kugel-Khomskii-type superexchange in π-electron systems determines the magnetostructural properties. These results establish a fruitful analogy between π- and more conventional 3d-mixed-valence systems and push the research of such systems into new directions to tackle the intertwining of various active degrees of freedom.”