ELECTRON-MOLECULE CLOSE COUPLING WITH CORRELATED TARGET WAVE-FUNCTIONS - APPLICATION TO IMPACT DISSOCIATION OF F2

An analysis of the close-coupling method as it is traditionally formulated for electron-scattering problems shows that it can give rise to spurious resonances at intermediate energies when multiconfiguration target states are used. These resonances are associated with excited states of the target that are not explicitly included in the close-coupling expansion. We develop a modification of the close-coupling technique that allows one to isolate and systematically eliminate terms from the total wave function which are responsiblefor the spurious behavior. We have applied this technique to the study of electron-impact dissociation of F2 through its two lowest excited states. The complex Kohn variational calculations we have performed on this system incorporate accurate, multiconfiguration descriptions of the target wave functions.