Autodetachment of doubly excited states in nonhydrogenic negative ions.

A semiclassical model is developed to describe the two-electron dynamics of the process of autodetachment. A formula derived for the partial width of a doubly excited state represents a product of an amplitude and phase factors. An anomalous width behavior is predicted for states near a threshold when the orbital angular momentum of the outer electron is high. Oscillations of the phase factor, as a function of energy, determine the functional behavior of relative widths in the region farther from threshold for a given series of states.