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

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.

7 peges, 7 figures, accepted for publication in Phys. Rev. B

References in corpus (3)

• Theoretical Aspects of Charge Ordering in Molecular Conductors
• Quantum Melting of Charge Order due to Frustration in Two-Dimensional Quarter-Filled Systems
• Effects of Electron-Lattice Coupling on Charge Order in θ-(ET)2X

Cited by in corpus (2)

• Coexistence of distinct charge fluctuations in $\theta$-(BEDT-TTF)${}_2$X
• Spin and Charge Fluctuations and Lattice Effects on Charge Orders in α-(BEDT-TTF)_2I_3