title: Photodissociation of thymine.
abstract: We discuss the photochemistry and photodissociation dynamics of thymine as revealed by two-colour photofragment Doppler spectroscopy and by one-colour slice imaging. Thymine is optically excited into the pipi* state, known to deactivate quickly. The H atom photofragment spectra are dominated by two-photon excitation processes with subsequent statistical dissociation. This can be explained by absorption of a second photon from a long-lived dark state to a highly excited state that quickly deactivates to the electronic ground state. No evidence was found for an important role of the pisigma* excited state identified in adenine and many other heterocyclic molecules.
authors.affiliation: Institute of Physical Chemistry, University of Würzburg, Am Hubland, D-97074, Würzburg.
authors.forename: Michael
authors.initials: M
authors.lastname: Schneider
authors.forename: Raman
authors.initials: R
authors.lastname: Maksimenka
authors.forename: F Johannes
authors.initials: FJ
authors.lastname: Buback
authors.forename: Theofanis
authors.initials: T
authors.lastname: Kitsopoulos
authors.forename: Luis R
authors.initials: LR
authors.lastname: Lago
authors.forename: Ingo
authors.initials: I
authors.lastname: Fischer
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D008027:Light; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D010777:Photochemistry / Q000379:methods*; D011789:Quantum Theory; D013941:Thymine / Q000737:chemistry* / Q000528:radiation effects*
chemical_list: D013941:Thymine