Deactivation of Highly Excited CS2 and SO2 by Rare Gases

ALEXANDER CHIMBAYO,; BEATRIZ M. TOSELLI; JOHN R. BARKER

AMER INST PHYSICS

Año: 1998 p. 2383 - 2383

he time dependent thermal lensing ~TDTL! technique has been used to study collisional energytransfer from highly excited CS2 in baths of Xe, Kr, and Ar, and from highly excited SO2 in Kr andAr. Bath gas pressures ranged from about 50 to about 600 Torr. The data were analyzed bysimulating the observed TDTL signals with a unified hydrodynamic TDTL theory. The results areexpressed in terms of ^DE&, the bulk average energy transferred per collision as a function of ^E&,the mean energy content. The results show that ^DE& increases dramatically at ^E&'17 500? 23 500 cm21 for CS2 deactivation, and at ^E&'18 000? 22 500 cm21 for SO2deactivation. This enhancement of energy transfer, which was observed previously in NO2 and CS2deactivation, has been linked to the presence of nearby excited electronic states. Furthermore, atlower energy, our results reveal an unusual systematic dependence of ^DE& on bath pressure; ener