Phase evolution of layered cobalt oxides versus varying corrugation of the 
cobalt-oxygen basal plane

Wu, H.

Item

ITEM ACTIONSEXPORT

Add to Basket

Local TagsRelease HistoryDetailsSummary

Released

Journal Article

Phase evolution of layered cobalt oxides versus varying corrugation of the cobalt-oxygen basal plane

MPS-Authors

/persons/resource/persons185064

Wu, H.
Max Planck Institute for the Physics of Complex Systems, Max Planck Society;

External Resource

No external resources are shared

Fulltext (restricted access)

There are currently no full texts shared for your IP range.

Fulltext (public)

There are no public fulltexts stored in PuRe

Supplementary Material (public)

There is no public supplementary material available

Citation

Wu, H. (2002). Phase evolution of layered cobalt oxides versus varying corrugation of the cobalt-oxygen basal plane. European Physical Journal B, 30(4), 501-510. Retrieved from http://link.springer.de/link/service/journals/10051/bibs/2030004/20300501.htm.

Cite as: https://hdl.handle.net/11858/00-001M-0000-002B-3697-1

Abstract

A general spin-state model and a qualitative physical picture have been proposed for a class of lately synthesized layered cobalt oxides (LCOs) by means of density functional calculations. As the plane corrugation of the cobalt-oxygen layer decreases, the LCOs evolve from a high-spin (HS) superexchange-coupled antiferromagnetic (AFM) insulator to an almost-HS AFM/ferromagnetic (FM) competing system where the FM coupling is mediated via the p-d exchange by an increasing amount of delocalized pdsigma holes having mainly the planar 0 2p character. It is tentatively suggested that the delocalized holes more than 0.3 per CoO2 basal square are likely necessary for the insulator-metal and/or AFM-FM transitions in the corrugation-weakened LCOs. A phase control may be realized in LCOs by varying the plane corrugation (thus modifying the hole concentration) through an ionic-size change of the neighboring layers on both sides of the cobalt-oxygen layer. In addition, a few experiments are suggested for a check of the present model and picture.