Multielectron effects on single-electron strong field ionization

An apparently simple phenomenon of single-electron strong field ionization involves subtle factors related to multielectron effects. A single electron in an atom or molecule can feel a distinctly different screening strength when exposed to strong fields as opposed to weak fields, and this electron screening due to multielectron motion influences single-electron ionization. The concept and a corresponding model developed in the paper allow a generalization of the Ammosov-Delone-Krainov model for predicting strong field ionization rates of more complicated atoms and molecules. This general approach explains the recently observed anomalous low single ionization rate in O-2.