Effect of electron exchange on atomic ionization in a strong electric field
M. Ya. Amusia
Racah Institute of physics, The Hebrew University, 91904 Jerusalem, Israel
Ioffe Physico-Technical Institute, 194021 St. Petersburg, Russia
PACS: 03.65.-w
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.