Themes > Science > Physics > Molecular Physics > Excitation Energy Transfer and Energy Migration > Resonances and negative ions > Negative ions and Photodetachment

In negative ions the last electron is, in general, bound only due to the dipole part of the electron-electron interaction, which is attractive. Many negative ions have just one bound state but often also long-lived resonance states exist which can be observed in photodetachment studies. We have worked with H- and Li- and recently also with He- which has been treated from first principles as a full three-body system.



Fig. The lowest energy doubly excited 4S-states of He-.