Quantum mechanics

Chemical physics

Photochemistry

Electron capture

Materials science

Social psychology

Atomic physics

Dissociation (chemistry)

Picosecond

Physical chemistry

Laser

Physics

Organic chemistry

Psychology

Optics

Molecular physics

Relaxation (psychology)

Solvated electron

Radical

Excited state

Radiolysis

Chemistry

Electron

Photodissociation

Nature Communications

Damage to DNA via dissociative electron attachment has been well-studied in both the gas and condensed phases; however, understanding this process in bulk solution at a fundamental level is still a challenge. Here, we use a picosecond pulse of a high energy electron beam to generate electrons in liquid diethylene glycol and observe the electron attachment dynamics to ribothymidine at different stages of electron relaxation. Our transient spectroscopic results reveal that the quasi-free electron with energy near the conduction band effectively attaches to ribothymidine leading to a new absorbing species that is characterized in the UV-visible region. This species exhibits a nearly concentration-independent decay with a time constant of ~350 ps. From time-resolved studies under different conditions, combined with data analysis and theoretical calculations, we assign this intermediate to an excited anion radical that undergoes N1-C1' glycosidic bond dissociation rather than relaxation to its ground state.

Observation of dissociative quasi-free electron attachment to nucleoside via excited anion radical in solution