Dynamics of Charge Transfer in DNA Wires: A Proton-Coupled Approach

The advent of molecular electronics has fueled interest in studying DNA as a nanowire. The well - known Peyrard Bishop - Dauxois (PBD) model, which was proposed for the purpose of understanding the mechanism of DNA denaturation, has a limited number of degrees of freedom. In addition, considering the Peyrard - Bishop - Holstein (PBH) model as a means of studying the charge transfer effect, in which the dynamical motion is described via the PBD model, may apply limitations on observing all the phenomena. Therefore, we have attempted to add the mutual interaction of a proton and electron in the form of proton - coupled electron transfer (PCET) to the PBH model. PCET has been implicated in a variety of oxidative processes that ultimately lead to mutations. When we have considered the PCET approach to DNA based on a proton - combined PBH model, we were able to extract the electron and proton currents independently. In this case, the reciprocal influence of electron and proton current is considered. This interaction does not affect the general form of the electronic current in DNA, but it changes the threshold of the occurrence of phenomena such as negative differential resistance. It is worth mentioning that perceiving the structural properties of the attractors in phase space via the Renyi dimension and concentrating on the critical regions through a scalogram can present a clear picture of the critical points in such phenomena.