Abstract
We consider the superstructures, which can be formed in spinels containing on sites the transition-metal ions with partially filled levels. We show that, when such systems are close to the itinerant state (e.g., have an insulator-metal transition), there may appear in them an orbitally driven Peierls state. We explain by this mechanism the very unusual superstructures observed in (octamers) and (chiral superstructures) and suggest that a similar phenomenon should be observed in and possibly in some other systems.
- Received 17 May 2004
DOI:https://doi.org/10.1103/PhysRevLett.94.156402
©2005 American Physical Society