Excited-State Proton-Transfer Processes of DHICA Resolved: From Sub-Picoseconds to Nanoseconds.

@article{Corani2013ExcitedStatePP,
  title={Excited-State Proton-Transfer Processes of DHICA Resolved: From Sub-Picoseconds to Nanoseconds.},
  author={Alice Corani and Alessandro Pezzella and Torbj{\"o}rn Pascher and Thomas Gustavsson and Dimitra Markovitsi and Annemarie Huijser and Marco d'Ischia and Villy Sundstr{\"o}m},
  journal={The journal of physical chemistry letters},
  year={2013},
  volume={4 9},
  pages={1383-8}
}
Excited-state proton transfer has been hypothesized as a mechanism for UV energy dissipation in eumelanin skin pigments. By using time-resolved fluorescence spectroscopy, we show that the previously proposed, but unresolved, excited-state intramolecular proton transfer (ESIPT) of the eumelanin building block 5,6-dihydroxyindole-2-carboxylic acid (DHICA) occurs with a time constant of 300 fs in aqueous solution but completely stops in methanol. The previously disputed excited-state proton… CONTINUE READING