Effect of electron exchange on atomic ionization in a strong electric field

TL;DR

This paper demonstrates that electron exchange significantly enhances the ionization probability of inner electrons in atoms subjected to strong electric fields, especially in clusters, by altering the wave function's long-range behavior.

Contribution

It reveals that exchange effects dramatically increase inner electron ionization rates in strong fields, a factor previously underestimated in atomic and cluster physics.

Findings

Exchange effects increase ionization probability by many orders of magnitude.

Inner electron ionization probability scales with the square of the number of outer electrons.

Inner electron ionization in clusters is significantly higher than in isolated atoms.

Abstract

Hartree-Fock atom in a strong electric static field is considered. It is demonstrated that exchange between outer and inner electrons, taken into account by the so-called Fock term affects strongly the long-range behavior of the inner electron wave function. As a result, it dramatically increases its probability to be ionized. A simple model is analyzed demonstrating that the decay probability, compared to the case of a local (Hartree) atomic potential, increases by many orders of magnitude. As a result of such increase, the ratio of inner to outer electrons ionization probability became not too small. It is essential that the effect of exchange upon probability of inner electron ionization by strong electric field is proportional to the square of the number of outer electrons. It signals that in clusters the inner electron ionization by strong field, the very fact of which is manifested by e.g. high energy quanta emission, has to be essentially increased as compared to this process in gaseous atomic objects.