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arXiv · 1104.0113

Magnetism and Charge ordering in TMTTF$_2$-PF$_6$ organic crystals

Gianluca Giovannetti·Sanjeev Kumar·Jean-Paul Pouget·Massimo Capone
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Abstract

Using a combination of Density Functional Theory, mean-field analysis and exact diagonalization calculations we reveal the emergence of a dimerized charge ordered state in TMTTF$_2$-PF$_6$ organic crystal. The interplay between charge and spin order leads to a rich phase diagram. Coexistence of charge ordering with a structural dimerization results in a ferroelectric phase, which has been observed experimentally. The tendency to the dimerization is magnetically driven revealing TMTTF$_2$-PF$_6$ as a multiferroic material.

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Gianluca Giovannetti, Sanjeev Kumar, Jean-Paul Pouget, Massimo Capone. 2011-04-01. Magnetism and Charge ordering in TMTTF$_2$-PF$_6$ organic crystals. https://doi.org/10.1103/physrevb.85.205146

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