Shapir, E., Cohen, H., Calzolari, A., Cavazzoni, C., Ryn- dyk, D.A., Cuniberti, G., Kotlyar, A.B., Di Felice, R. and Porath, D. (2008) Electronic structure of single DNA mo- lecules resolved by transverse scanning tunnelling spec- troscopy. Nature Materials, 7(1), 68-74.

has been cited by the following article:

• TITLE: Distance-dependent coherent charge transport in DNA: crossover from tunneling to free propagation

  AUTHORS: Natallia V. Grib, Dmitry A. Ryndyk, Rafael Gutiérrez, Gianaurelio Cuniberti

  KEYWORDS: DNA; Electron Transport; Modeling of DNA; Electronic Structure of DNA

  JOURNAL NAME: Journal of Biophysical Chemistry, Vol.1 No.2, September 7, 2010

  ABSTRACT: Using a tight-binding model, we investigate the influence of intra- and interstand coupling parameters on the charge transport properties in a G-(T)j-GGG DNA sequence and its (G:C)-(T:A)j-(G:C)3 duplex attached to four electrodes. Dependences of the transmission function and of the corresponding conductance of the system on the number of bridging sites were obtained. Simulation results of a recently proposed two-strand superexchange (tunneling) model were reproduced and extended. It is demonstrated that the crossover from strong to weak distance-dependent charge transport is elucidated by a transition from under-barrier tunneling mechanism to free over-barrier propagation in the coherent regime, controlled by temperature and coupling parameters. The role of DNA- electrode coupling has been also considered. It was found that an asymmetry in the DNA-electrode coupling has a drastic effect on the con-ductance leading to an increase in delocaliza-tion of the electronic states in the DNA duplex.