Using Real-Time TDDFT to Study High Energy Particle Irradiation in Solvated DNA
University of North Carolina at Chapel Hill
Understanding the electronic excitation response of DNA to charged particle radiation, such as high-energy protons and α-particles, has become increasingly important, particularly with recent advances in ion-beam cancer therapy. Unlike photons, high-energy particles show a highly localized energy deposition profile and can more precisely target tumor cells without damaging surrounding healthy cells. However, how protons and α-particles induce DNA damage is not understood at the molecular level. Here we use the Qb@ll/Qbox code and real-time time-dependent density functional theory (RT-TDDT) to simulate the complex electronic excitation in solvated DNA. In particular, we propagate the time-dependent maximally-localized Wannier functions (TD-MLWFs) to provide key insights at the molecular-level. Our results show significantly more energy is deposited onto the sugar-phosphate side chains, generating highly energetic holes and likely causing strand damage.