Final Report Summary - DEX (DNA Excitonics)
During the course of this project, progress in both experiment and theory was achieved in the host institution. Experimentalists developed a new optical technique (UV 2DES spectroscopy), which enabled unprecedented new measurements of the photophysics of nucleobases. This work led to the surprising insight that all four nucleobases show similar behaviour, and that an intermediate dark electronic state is involved in the ultrafast relaxation process. Stimulated and guided by these experimental insights, the contribution from this Marie Curie project was to develop a new theoretical method to enable comparison with experiment. In detail, the new calculations propagate damped dynamics in a model system with two conical intersections. In close collaboration with experimental colleagues, model parameters were optimized by calculating observables and directly comparing those with experimental results. The outcome of this effort is an increased understanding of the principles that underlie the photostability of DNA nucleobases.