TY - JOUR AU - Pozdnyakov, Ivan P. AU - Pigliucci, Anatolio AU - Tkachenko, Nikolai AU - Plyusnin, Victor F. AU - Vauthey, Eric AU - Lemmetyinen, Helge TI - The photophysics of salicylic acid derivatives in aqueous solution PY - 2009 JF - Journal of Physical Organic Chemistry JA - J. Phys. Org. Chem. SN - 0894-3230 VL - 22 IS - 5 SP - 449 EP - 454 L1 - http://www3.interscience.wiley.com/cgi-bin/fulltext/121542630/PDFSTART L3 - http://www3.interscience.wiley.com/journal/121542630/abstract?CRETRY=1&SRETRY=0 M3 - 10.1002/poc.1489 UR - http://dx.doi.org/10.1002/poc.1489 N2 - The photophysics of a number salicylic acid derivatives (SADs) in aqueous solutions was investigated in a wide range of pH by time-correlated single photon counting (λex = 350 nm, τresp = 300 ps) and fluorescence up-conversion (λex = 266 nm, τresp = 300 fs) techniques. The acid-base equilibrium constants in the ground (pKa) and the excited states (pKa*), the fluorescence quantum yields as well as the lifetimes of anionic, neutral, and cationic forms of SADs were determined. Evidence of ultrafast excited-state intramolecular proton transfer (ESIPT) leading to the formation of the proton-transferred excited state of SADs was obtained from the fluorescence up-conversion measurement. The nature of the ESIPT process is discussed. ID - 981 ER -