Semiclassical dynamics of electron attachment to guanine–cytosine base pair

Abstract

Electron attachment dynamics to the guanine–cytosine (G–C) base pair in the gas phase is studied using DFT and molecular dynamics. The potential energy surface of the G–C anion is constructed with the empirical-valence-bond method using force-field information obtained from long-range corrected DFT calculations. Ring-polymer molecular dynamics simulations predict that the initial dipole-bound anion readily converts into the valence-bound anion within 0.1ps and proton-transfer occurs subsequently within 10ps. The same process was found in classical simulations, but on a much slower time scale. This result suggests that nuclear quantum effects are important in understanding DNA damage by low-energy electrons.