  In this report, the impact of the Casimir effect in the near-nuclear
environment on electrons, in particular of the K-shell, is investigated. It has
long been known that the experimentally measured binding energies of the inner
electrons, especially for heavy elements, agree only to a very limited extent
with the theoretical solutions of the Schroedinger and Dirac equations. This
report presents a modification for the potential of electrons near the nucleus
by investigating the impact of the Casimir effect on the innermost electrons.
It can be shown that with this approach the calculated binding energies agree
much better with the literature values from spectroscopy, especially for heavy
elements. In addition, the innermost electrons are apparently influenced much
more strongly than previously assumed by the nature of the nuclear surface, in
particular the deviation from the spherical geometry, e.g. the multipole
moments and not least the range of the strong interaction. This effect is not
to be confused with the quantum-mechanical quadrupole energy (Casimir 1936),
which is determined by spin interactions between nucleus and electron, but the
effect discussed in this report is a distance dominated effect of the
s-electrons to the nucleus. It offers the possibility of investigating the
nucleus structure and isotope effects on the binding energies much more
precisely than expected, e.g. by spectroscopy, and thus gaining new insights
into the respective nuclear structure and geometry. At the same time, this
approach shows that the probability of the electrons staying close to the
nucleus is apparently significantly higher than assumed in previous atomic
models. This may also increase the transition probabilities of electron
capture, and thus the model enables a higher accuracy for the calculation of
the theoretical half lifetimes for electron capture decay.
