Abstract
Ultrahigh resolution synchrotron diffraction data for throw new light on the metal-insulator transition of Ba-cobaltites. An anomalous expansion of octahedra is observed at the phase transition on heating, while pyramids show the normal shrinking at the closing of the gap. The insulator-to-metal transition is attributed to a sudden excitation of some electrons in the octahedra state) into the Co band (final state). The state in the pyramids does not change and the structural study also rules out a orbital ordering at
- Received 8 January 2002
DOI:https://doi.org/10.1103/PhysRevB.65.180405
©2002 American Physical Society