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arXiv · 0909.5658

First principles determination of the model parameters in $κ$-(ET)$_2$Cu$_2$(CN)$_3$

Harald O. Jeschke·Hem C. Kandpal·Ingo Opahle·Yu-Zhong Zhang·Roser Valenti
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Abstract

We present a detailed study of the derivation of the Hubbard model parameters for $κ$-(ET)$_2$Cu$_2$(CN)$_3$ in the framework of {\it ab initio} Density Functional Theory. We show that calculations with different (i) wavefunction basis, (ii) exchange correlation functionals and (iii) tight-binding models provide a reliable benchmark for the parameter values. We compare our results with available extended Hückel molecular orbital calculations and discuss its implications for the description of the properties of $κ$-(ET)$_2$Cu$_2$(CN)$_3$. The electronic properties of $κ$-(ET)$_2$Cu(SCN)$_2$ are also briefly discussed.

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Harald O. Jeschke, Hem C. Kandpal, Ingo Opahle, Yu-Zhong Zhang, Roser Valenti. 2009-09-30. First principles determination of the model parameters in $κ$-(ET)$_2$Cu$_2$(CN)$_3$. https://doi.org/10.1016/j.physb.2009.12.055

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