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Charge transfer via a two-strand superexchange bridge in DNA

X. F. Wang·Tapash Chakraborty
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Abstract

Charge transfer in a DNA duplex chain is studied by constructing a system with virtual electrodes connected at the ends of each DNA strand. The systeym is described by the tight-binding model and its transport is analyzed by the transfer matrix method. The very weak distance dependence in long (G:C)(T:A)_M(G:C)_3 DNA chain observed in experiment [B. Giese, et al., Nature 412, 318 (2001)] is explained by a unistep two-strand superexchange bridge without the need for the multi-step thermally-induced hopping mechanism or the dephasing effect. The crossover number M_c of (T:A) base pairs, where crossover between strong and weak distance dependence occurs, reflects the ratio of intra- and inter-strand neighboring base-base couplings.

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X. F. Wang, Tapash Chakraborty. 2006-09-01. Charge transfer via a two-strand superexchange bridge in DNA. https://doi.org/10.1103/physrevlett.97.106602

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