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Electron-lattice coupling and the broken symmetries of the molecular salt (TMTTF)$_2$SbF$_6$

W. Yu·F. Zhang·F. Zamborszky·B. Alavi·A. Baur·C. A. Merlic·S. E. Brown
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Abstract

(TMTTF)$_2$SbF$_6$ is known to undergo a charge ordering (CO) phase transition at $T_{CO}\approx156K$ and another transition to an antiferromagnetic (AF) state at $T_N\approx 8K$. Applied pressure $P$ causes a decrease in both $T_{CO}$ and $T_N$. When $P>0.5 GPa$, the CO is largely supressed, and there is no remaining signature of AF order. Instead, the ground state is a singlet. In addition to establishing an expanded, general phase diagram for the physics of TMTTF salts, we establish the role of electron-lattice coupling in determining how the system evolves with pressure.

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W. Yu, F. Zhang, F. Zamborszky, B. Alavi, A. Baur, C. A. Merlic, S. E. Brown. 2004-05-28. Electron-lattice coupling and the broken symmetries of the molecular salt (TMTTF)$_2$SbF$_6$. https://doi.org/10.1103/physrevb.70.121101

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