Total angular momentum and decay of unimolecular resonances - IVR-mediated vibrational predissociation

Full-dimensional wavepacket calculations are carried out on the vibrational predissociation of ArI2. With the aid of a parallel computing strategy, we consider systems with total angular momentum quantum numbers up to J = 24. Previous work for low J has shown that fragmentation occurs via a sparse limit intramolecular vibrational energy redistribution mechanism involving passage through a few intermediate dark states. Despite many more states becoming available as J is increased, this mechanism continues to dominate. Inspection of wavepacket densities and characterization of the dark states helps explain why the mechanism persists with increasing J.