Coherence effects between intramolecular vibrational relaxation and dissociation in triatomic van der Waals systems

Time-independent [Halberstadt and co-workers, J. Chem. Phys. 96, 2404 (1992); 97, 341 (1992)] and time-dependent quantum mechanical calculations that describe the intramolecular vibrational relaxation (IVR) of Ar...Cl2 are used to develop analytical models for this process. It is shown that time-resolved experiments should reveal an oscillatory dissociation rate. It is found that the oscillations will be different for different rotational levels, and may tend to wash out if insufficient state selection is achieved in the initial excitation step. This may explain why no such oscillations were observed for Ar...I2. It is also predicted that the observed product state rotational distribution will change with the initially excited rotational state.