Long-range Charger transfer in DNA through Polaron Diffusion

Recent experimental evidence shows that the pi-orbitals along the stacking of base pairs can facilitate the long-range charge transfer in DNA. Proton motion in the base pair hydrogen bonds has also been found to affect the transfer rate. To explain this behavior we propose a model considering interactions of doped charges with hydrogen bonds and vibrations in DNA. The charge trapped by either protons or vibrations can cause structural distortions leading to polaron formation. By further considering polaron diffusion in DNA we find that the charge transfer rate derived from the diffusion coefficient is in agreement with the experimental results.