The reaction of a xenon atom with a chlorine molecule has been studied
in the femtosecond regime using the pump (395 nm) and probe (308 nm)
technique in Xe-Cl-2 clusters. The electronically excited reaction pro
duct XeCl was observed both after a simultaneous and a sequential (wit
h a delay of approximate to 500 fs) absorption of the pump and probe p
hotons. (C) 1996 American Institute of Physics.