Excimer Intermediates en Route to Long-Lived Charge-Transfer States in Single-Stranded Adenine DNA as Revealed by Nonadiabatic Dynamics
Lea M. Ibele, Pedro A. Sánchez‐Murcia, Sebastian Mai, Juan J. Nogueira, Leticia González
Abstract
where a stacked adenine tetramer is treated quantum chemically. The dynamical simulations combined with on-the-fly quantitative wave function analysis evidence the nature of the long-lived electronically excited states formed upon absorption of UV light. After a rapid decrease of the initially excited excitons, relaxation to monomer-like states and excimers occurs within 100 fs. The former monomeric states then relax into additional excimer states en route to forming stabilized charge-transfer states on a longer timescale of hundreds of femtoseconds. The different electronic-state characters is reflected on the spatial separation between the adenines: excimers and charge-transfer states show a much smaller spatial separation than the monomer-like states and the initially formed excitons.