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arXiv · 0803.3886

Towards a theoretical description of molecular junctions in the Coulomb blockade regime based on density functional theory

R. Stadler·V. Geskin·J. Cornil
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Abstract

Non-equilibrium Greens function techniques (NEGF) combined with Density Functional Theory (DFT) calculations have become a standard tool for the description of electron transport through single molecule nano-junctions in the coherent tunneling regime. However, the applicability of these methods for transport in the Coulomb blockade (CB) regime is still under debate. We present here NEGF-DFT calculations performed on simple model systems in the presence of an effective gate potential. The results show that: i) the CB addition energies can be predicted with such an approach with reasonable accuracy; ii) neither the magnitude of the Kohn-Sham gap nor the lack of a derivative discontinuity in the exchange-correlation functional represent a problem for this purpose.

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R. Stadler, V. Geskin, J. Cornil. 2008-03-27. Towards a theoretical description of molecular junctions in the Coulomb blockade regime based on density functional theory. https://doi.org/10.1103/physrevb.78.113402

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