Time-resolved photoelectron spectroscopy of molecular dissociation: Classical trajectory versus quantum wave-packet calculations

Abstract

We present a simulation of ultrafast pump–probe photoelectron spectroscopy based on a classical treatment of the nuclear motion. A comparison with quantum mechanical wave-packet results shows that in the case of the direct dissociation of H₂O in its à ¹B₁ electronic state this method produces extremely accurate results. The energy distribution of the photoelectrons recorded as a function of the pump–probe delay reflects the dissociation process, which takes place within only a few femtoseconds.