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Published on: December 3, 2013
Cooperative jahn-teller coupling in the manganites
1Department of Physics & Astronomy, University of Missouri, Columbia, Missouri 65211, USA.
Physical Review Letters
|October 4, 2000
Summary
The Jahn-Teller coupling in LaMnO3 causes ordered distortions and orbital ordering, creating a two-minima potential surface instead of the typical three-minima surface.
Area of Science:
- Solid-state physics
- Materials science
- Quantum chemistry
Background:
- LaMnO3 exhibits complex electronic and structural properties.
- The Jahn-Teller effect is crucial for understanding orbital ordering in transition metal oxides.
Purpose of the Study:
- Investigate the cooperative Jahn-Teller coupling in LaMnO3.
- Determine the impact of this coupling on octahedral distortions and orbital ordering.
- Characterize the adiabatic potential surface.
Main Methods:
- Ab initio density-functional calculations.
- Tight-binding models.
- Calculation of linear and quadratic vibronic coupling parameters.
Main Results:
- Cooperative Jahn-Teller coupling drives octahedral distortion ordering.
- Simultaneous orbital ordering is a direct consequence of this coupling.
- The adiabatic potential surface shifts from three minima to two minima in the solid.
Conclusions:
- The interoctahedral electron hopping is the primary driver of the observed phenomena.
- The cooperative Jahn-Teller effect fundamentally alters the electronic and structural landscape of LaMnO3.
- This study provides insight into the mechanism of orbital ordering in perovskite manganites.
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