arXiv:1009.5312 · Physical Review B

Density functional theory based many-body analysis of electron transport through molecules

Fatemeh Mirjani, Joseph Marie Thijssen

Published Jan 20, 2011• 20 citations

Abstract

We present a method which uses density functional theory (DFT) to treat transport through a single molecule connected to two conducting leads for the weak and intermediate coupling. This case is not accessible to standard nonequilibrium Green's function calculations. Our method is based on a mapping of the Hamiltonian on the molecule to a limited set of many-body eigenstates. This generates a many-body Hamiltonian with parameters obtained from ground-state local (spin) density approximation-DFT calculations. We then calculate the transport using many-body Green's function theory. We compare our results with existing density matrix renormalization group calculations for spinless and for spin-1/2 fermion chains and find good agreement.

DOI: 10.1103/physrevb.83.035415

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