Dynamics of Dissociation. I. Computational Investigation of Unimolecular Breakdown Processes

Abstract

An explicit method for the exact calculation of unimolecular linewidths and line shapes, using an adaptation of known numerical techniques, is presented. The method renders feasible the calculation of decay from one composite ``bound'' subspace, into another composite ``continuum'' subspace. The eigenvalues of the Hamiltonian for the whole ``bound'' subspace are also obtained to a high degree of accuracy. Two specific examples are studied: (a) A single closed channel (containing four bound states) coupled to a single open channel, and (b) three closed channels corresponding to eight bound states, interacting with a single open channel. The exact line shapes for the first of these cases are computed. Interference effects, due to overlapping resonances, are clearly demonstrated and discussed in terms of Fano's theory. Line‐widths and resonance energies are calculated for the second case. The results are contrasted to those of the related scattering problem and discussed in terms of the different boundary conditions.