Mechanism and deactivation kinetics of S2-xanthione in acetonitrile, a quenching solvent, and of S2-exciplex measured by pico- and femtosecond laser spectroscopy

摘要: Abstract The Letter discusses the mechanism and dynamics of intra- intermolecular electronic relaxation S 2 state a xanthione molecule in acetonitrile, quenching solvent, as well most important properties -exciplex formed upon process. Despite very efficient -XT other thiones it has not been possible so far to observe -exciplex. Therefore transient absorption system with 120 fs resolution was successfully applied for this purpose: identified first time, its lifetime (∼30 ps) spectrum were determined formation decay. Moreover, authors observed presence fast intramolecular process (S v >0 →S 0 ) during -state deactivation which competes vibrational redistribution -state.