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arXiv · 0704.3033

Charge ordering in θ-(BEDT-TTF)2RbZn(SCN)4: Cooperative effects of electron correlations and lattice distortions

Satoshi Miyashita·Kenji Yonemitsu
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Abstract

Combined effects of electron correlations and lattice distortions are investigated on the charge ordering in θ-(BEDT-TTF)2RbZn(SCN)4 theoretically in a two-dimensional 3/4-filled extended Hubbard model with electron-lattice couplings. It is known that this material undergoes a phase transition from a high-symmetry metallic state to a low-symmetry insulating state with a horizontal-stripe charge order (CO) by lowering temperature. By means of the exact-diagonalization method, we show that electron-phonon interactions are crucial to stabilize the horizontal-stripe CO and to realize the low-symmetry crystal structure.

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Satoshi Miyashita, Kenji Yonemitsu. 2007-04-23. Charge ordering in θ-(BEDT-TTF)2RbZn(SCN)4: Cooperative effects of electron correlations and lattice distortions. https://doi.org/10.1103/physrevb.75.245112

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