On Charge Transfer In DNA

Various mechanisms of charge transfer in DNA are considered in this paper. Some of them, tunneling and jump mechanism, are impossible due to the rapid decrease of probability with increasing distance of transfer. Two models of charge transfer due to polarons are considered in detail. In both models (Peyrard-Bishop-Holstein and Su-Schrieffer-Heeger) the polaron is found to be unstable with respect to collapse due to large amplitudes of thermal fluctuations. On the basis of the available experimental results, an alternative mechanism of charge transfer, which is weakly sensitive to temperature changes, is considered.