Quantum wavepacket study of electron detachment from H- by electron impact

Electron detachment from negative hydrogen ions by low-energy electron impact is considered as an especially simple example to test the validity of a sequence of approximations that allow quantum wavepacket computations to be implemented with desktop facilities. In the present approach, the motion of the electron initially localized in the loosely bound ion state is treated quantum mechanically while the incident electron is assumed to move along a classical trajectory. In addition, the initial azimuthal symmetry is assumed to be conserved during the collision in the re-rotating frame such that the quantum motion is restricted to two degrees of freedom. The wave-dynamical approach is used directly to determine the electron detachment cross section. It also provides a valuable means to clarify physical aspects of the considered process. As examples, we show that the effective detachment rate is strongly affected by projectile-induced polarization effects and that non-adiabatic features are important for a complete account of the electron detachment process. The results of the wave-dynamic calculations are in excellent agreement with recent experimental data.