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Coulomb parameters and photoemission for the molecular metal TTF-TCNQ

Laura Cano-Cortés·Andreas Dolfen·Jaime Merino·Jörg Behler·Bernard Delley·Karsten Reuter·Erik Koch
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Abstract

We employ density-functional theory to calculate realistic parameters for an extended Hubbard model of the molecular metal TTF-TCNQ. Considering both intra- and intermolecular screening in the crystal, we find significant longer-range Coulomb interactions along the molecular stacks, as well as inter-stack coupling. We show that the long-range Coulomb term of the extended Hubbard model leads to a broadening of the spectral density, likely resolving the problems with the interpretation of photoemission experiments using a simple Hubbard model only.

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Laura Cano-Cortés, Andreas Dolfen, Jaime Merino, Jörg Behler, Bernard Delley, Karsten Reuter, Erik Koch. 2006-09-18. Coulomb parameters and photoemission for the molecular metal TTF-TCNQ. https://doi.org/10.1140/epjb%2Fe2007-00110-y

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