Singlet excited state dynamics of uracil and thymine derivatives: A femtosecond fluorescence upconversion study in acetonitrile

T. Gustavsson (1) , N. Sarkar (1) , E. Lazzarotto (1) , D. Markovitsi (1) , R. Improta (2)

1 LFP - URA 2453 - Laboratoire Francis PERRIN
2 Dipartimento di Chimica

The excited state properties of uracil, thymine and four analogous uracil compounds have been studied in acetonitrile by steady-state and time-resolved spectroscopy. The excited state lifetimes were measured using femtosecond UV fluorescence upconversion. The excited state lifetimes of uracil and its 1- and 3-methyl substituted derivatives are well described by one ultrafast (6100 fs) component. Five substituted compounds show a more complex behavior, exhibiting longer excited state lifetimes and bi-exponential fluorescence decays. These longer decays are substantially faster in acetonitrile than in aqueous solution showing that the excited state deactivation mechanism is in part governed by the solvent.

Domaines: Chimie théorique et/ou physique

T. Gustavsson, N. Sarkar, E. Lazzarotto, D. Markovitsi, R. Improta. Singlet excited state dynamics of uracil and thymine derivatives: A femtosecond fluorescence upconversion study in acetonitrile. Chemical Physics Letters, 2006, 429, pp.551-557. ⟨10.1016/j.cplett.2006.08.058⟩. ⟨hal-00098348⟩