ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
The dissociation dynamics of the cluster Li(H2)2, following the 2s→2p excitation of the Li atom, is studied in the framework of a collinear model. The process was investigated by exact quantum wave packet calculations, and the results were used to test a hybrid quantum/classical method, in which the highly quantum mechanical initial state of the cluster is described by a wave function, and the latter is used to sample initial positions and momenta for a classical treatment of the excited state dynamics. We found that the dynamics was dominated by two predissociation processes, Li*(H2)2→Li*–H2+H2 and Li*(H2)2→Li*+(H2)2, with the latter process having a higher yield. A relatively long dissociation lifetime, ∼10 ps, was found for the excited cluster. The slow vibrational predissociation rate was interpreted as due to the very low density of state involved. The hybrid quantum/classical approach was found to give product vibrational energy and velocity distributions in good accord with the distribution from exact calculation. However, the lifetimes from the hybrid approach were found to be much shorter than those from the exact quantum calculations. The hybrid approach is thus applicable even to photoexcitation of quantum clusters for studying certain selected properties. © 1995 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.468533
