Nuclear quantum effects on electron transfer reactions in DNA hairpins

The driving force dependence of photoinduced electron transfer rate constant in synthetic DNA hairpins in aqueous solutions has been analyzed by means of molecular dynamics simulations. The quantum energy gap law has thus been investigated from a fully atomistic point of view, well reproducing the experimental results with reduced ambiguities in the parameter fitting. Although the contribution from the high-frequency vibrational modes of DNA and water solvent to the reorganization energy is fairly small, their quantum effect on the electron transfer rate constant is significant, well accounting for the deviation from the Marcus parabola observed in the experiments.