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arXiv · 1110.3575

Spin frustration, charge ordering, and enhanced antiferromagnetism in TMTTF$_2$SbF$_6$

Kazuyoshi Yoshimi·Hitoshi Seo·Shoji Ishibashi·Stuart E. Brown
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Abstract

We theoretically investigate the effects of charge order and spin frustration on the spin ordering in TMTTF salts. Using first-principles band calculations, we find that a diagonal inter-chain transfer integral $t_{q1}$, which causes spin frustration between the inter-chain dimers in the dimer-Mott insulating state, strongly depends on the choice of anion. Within the numerical Lanczos exact diagonalization method, we show that the ferroelectric charge order changes the role of $t_{q1}$ from the spin frustration to the enhancement of the two-dimensionality in spin sector. The results indicate that $t_{q1}$ assists the cooperative behavior between charge order and antiferromagnetic state observed in TMTTF$_2$SbF$_6$.

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Kazuyoshi Yoshimi, Hitoshi Seo, Shoji Ishibashi, Stuart E. Brown. 2012-02-03. Spin frustration, charge ordering, and enhanced antiferromagnetism in TMTTF$_2$SbF$_6$. https://doi.org/10.1016/j.physb.2012.01.029

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