Structural fluctuations and quantum transport through DNA molecular wires: a combined molecular dynamics and model Hamiltonian approach

摘要

Charge transport through a short DNA oligomer (Dickerson dodecamer) inpresence of structural fluctuations is investigated using a hybridcomputational methodology based on a combination of quantum mechanicalelectronic structure calculations and classical molecular dynamics simulationswith a model Hamiltonian approach. Based on a fragment orbital description, theDNA electronic structure can be coarse-grained in a very efficient way. Theinfluence of dynamical fluctuations arising either from the solventfluctuations or from base-pair vibrational modes can be taken into account in astraightforward way through time series of the effective DNA electronicparameters, evaluated at snapshots along the MD trajectory. We show that chargetransport can be promoted through the coupling to solvent fluctuations, whichgate the onsite energies along the DNA wire.