Regensburg 2010 – wissenschaftliches Programm

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TT: Fachverband Tiefe Temperaturen

TT 35: TR: Nanoelectronics III: Molecular Electronics 1

TT 35.3: Vortrag

Donnerstag, 25. März 2010, 14:30–14:45, H21

Charge transfer characteristics of dsDNA with base mismatch in a solvent — •Myeong H Lee, Stanislav M Avdoshenko, Daijiro Nozaki, Rafael Gutierrez, and Gianaurelio Cuniberti — Institute for Materials Science and Max Bergmann Center of Biomaterials, Dresden University of Technology, 01062, Dresden, Germany

We present charge transfer characteristics of DNA by evaluating the electronic parameters in the presence of water and counterions. Motivated by the recent experiment by Guo et al. [1], we investigate three types of dsDNA oligomers; a well matched 15 base pair sequence and single mismatched base pairs (GT, CA) in sequence. Charge transfer parameters are obtained using a fragment orbital approach [2] on the coarse-grained level, where a fragment consists of a pair of nucleotides from each DNA strand. In order to fully take into account the effect of dynamical fluctuations [3] the electronic structure calculation is performed using a hybrid QM/MM method for each snapshot along the MD trajectory. From the electronic structure parameters the current is obtained for both coherent and incoherent transport [4] contribution to see the effect of single base pair mismatch.

[1] X. Guo et al., Nature Nanotech. 3, 163 (2008).

[2] D. G. Fedorov et al., J. Phys. Chem. A 111, 6904 (2007).

[3] R. Gutierrez, et al., Phys. Rev. Lett. 102, 208102 (2009); P. B. Woiczikowski et al., J. Chem. Phys. 130, 215104 (2009); P. B. Woiczikowski et al., J. Phys. Chem. B 112, 7937 (2008).

[4] J. L. D’Amato et al., Phys. Rev. B 41, 7411 (1990).