INFIQC   05475
INSTITUTO DE INVESTIGACIONES EN FISICO- QUIMICA DE CORDOBA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Excited-state multiple-proton transfer in solvated 7-azaindole clusters
Autor/es:
K. SAKOTA; H. SEKIYA; C. JOUVET; C. DEDONDER-LARDEUX; M. FUJII; G. A. PINO
Lugar:
Honolulu - Hawaii - USA
Reunión:
Simposio; Pacifichem 2010 - 87 Spectroscopic Probes of Intramolecular and Intermolecular Interactions in Molecules and Molecular clusters; 2010
Resumen:
Picoseconds pump and probe experiment has been applied to study the excited state dynamics of 7-azaindole-water 1:2 and 1:3 clusters [7AI(H2O)2,3] in the gas phase. The vibration-mode selective Excited-State-Triple-Proton Transfer (ESTPT) in 7AI(H2O)2 proposed from the frequency-resolved study has been confirmed by picosecond decays. The decay times for the vibronic states involving the ESTPT promoting mode s(1) (850~1000 ps) are much shorter than those for the other vibronic states (2100~4600 ps). In the (1+1) REMPI spectrum of 7AI(H2O)3 measured by nanosecond laser pulses, the vibronic bands with an energy higher than 200 cm-1 above the origin of the S1 state become very weak. In contrast, the vibronic bands in the same region emerge in the (1+1) REMPI spectrum of 7AI(H2O)3 with picoseconds pulses. The decay times drastically decreases when increasing the vibrational energy above 200 cm-1. Ab-initio calculations show that a second stable cyclic- nonplanar isomer exists in addition to bridged-planar isomer, and that an isomerization from bridged-planar isomer to cyclic-nonplanar isomer is most probably responsible for the short lifetimes of the vibronic states of 7AI(H2O)3.