We present a hybrid method based on a combination of quantum/classical molecular dynamics (MD) simulations [1] and a model Hamiltonian approach to describe charge transport through biomolecular wires [2]. Our approach maps the molecular electronic structure (obtained from the MD simulations) onto a tight-binding model. The latter is then coupled to a bosonic bath which describes fluctuation effects from the solvent and from the conformational dynamics. We apply this approach to the case of pG-pC and pA-pT oligomers as typical cases. We show that conformational fluctuations are crucial in determining charge transport. Especially, our results indicate that pA-pT shows a much larger current than pG-pC, in contrast to transport calculations performed on static configurations.
[1] T. Kubar, P. B. Woiczikowski, G. Cuniberti, and M. Elstner, J. Phys. Chem. B 112, 7937 (2008).
[2] R. Gutierrez, R. Caetano, B. Woiczikowski, T. Kubar, M. Elstner, G. Cuniberti, submitted (2008).
We present a hybrid method based on a combination of quantum/classical molecular dynamics (MD) simulations [1] and a model Hamiltonian approach to describe charge transport through biomolecular wires [2]. Our approach maps the molecular electronic structure (obtained from the MD simulations) onto a tight-binding model. The latter is then coupled to a bosonic bath which describes fluctuation effects from the solvent and from the conformational dynamics. We apply this approach to the case of pG-pC and pA-pT oligomers as typical cases. We show that conformational fluctuations are crucial in determining charge transport. Especially, our results indicate that pA-pT shows a much larger current than pG-pC, in contrast to transport calculations performed on static configurations.
[1] T. Kubar, P. B. Woiczikowski, G. Cuniberti, and M. Elstner, J. Phys. Chem. B 112, 7937 (2008).
[2] R. Gutierrez, R. Caetano, B. Woiczikowski, T. Kubar, M. Elstner, G. Cuniberti, submitted (2008).