Large amplitude ground state vibrational coherence induced by impulsive absorption in CsI. A computer simulation

Computer simulations are presented to show that impulsive optical excitation of CsI, in various vibrational levels, can give rise to large-amplitude vibrational coherence in the ground electronic state. It is further demonstrated that using transient absorption spectroscopy, such motion may be directly detected, and that this scheme should be experimentally realizable using currently available laser sources. The quantum mechanical propagation method used in this study, proves to be well suited for the simulation of optical excitation of small molecules, under conditions where the assumptions of time-dependent perturbation theory are violated.