Decay Pathways of Thymine Revisited

J. Phys. Chem. A, 2018, 122 (21), pp 4819–4828, DOI: 10.1021/acs.jpca.8b02050
J. Phys. Chem. A, online article


The decay of electronically excited states of thymine (Thy) and thymidine 5′-monophosphate (TMP) was studied by time-resolved UV/vis and IR spectroscopy. In addition to the well-established ultrafast internal conversion to the ground state, a so far unidentified UV-induced species is observed. In D2O, this species decays with a time constant of 300 ps for thymine and of 1 ns for TMP. The species coexists with the lowest triplet state and is formed with a comparably high quantum yield of about 10% independent of the solvent. The experimentally determined spectral signatures are discussed in the light of quantum chemical calculations of the singlet and triplet excited states of thymine.

TU München
Helmholtz München
MPI of Neurobiology
MPI of Biochemistry