First principles determination of the model parameters in $κ$-(ET)$_2$Cu$_2$(CN)$_3$
arXiv:0909.5658 · doi:10.1016/j.physb.2009.12.055
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.
Submitted to Special Issue - ISCOM 2009 - Physica B Condensed Matter