Unusual structural evolution in KCuF3 at high temperatures by neutron powder diffraction

Article

关键词: ORBITAL ORDER;    TRANSITION;    DENSITY;    HIPPO;   

DOI  :  10.1103/PhysRevB.87.014109

来源: SCIE

【 摘 要 】

High-resolution neutron powder diffraction has been performed to study the structural evolution of the perovskite KCuF3 at temperatures up to 900 K. Results of the Rietveld refinement reveal an unusual site distortion that increases as temperature increases. In contrast to the widely accepted assumption that a cooperative Jahn-Teller transition may occur at 800 K, no phase transition was observed up to 900 K. We have made a comparative study of the Jahn-Teller distortion in fluorides and oxides with variables such as temperature, pressure, and the dilution by non-Jahn-Teller active ions in these compounds.

【 授权许可】

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