Shape-resonance-enhanced nuclear motion effects in electron-molecule scattering and molecular photoionization

Shape resonances in the electronic continuum of molecules induce strong coupling between vibrational and electronic motion over a spectral range much broader than the resonance half width. In photoionization, this coupling causes large deviations from Franck-Condon intensity distributions and strong dependence of photoelectron angular distributions on the vibrational state of the residual ion. In electron scattering, it enhances vibrational excitation. The authors review recent work in which new, observable manifestations of this coupling have been predicted theoretically and then verified experimentally. (Auth.)