  In this work, the chemi-ionization processes in atom- Rydberg atom
collisions, as well as the corresponding chemi-recombination processes are
considered as factors of influence on the atom exited-state populations in
weakly ionized layers of stellar atmospheres. The presented results are related
to the photospheres of the Sun and some M red dwarfs as well as weakly ionized
layers of DB white dwarfs atmospheres. It has been found that the mentioned
chemi ionization/recombination processes dominate over the relevant concurrent
electron-atom and electron-ion ionization and recombination process in all
parts of considered stellar atmospheres. The obtained results demonstrate the
fact that the considered chemi ionization/recombination processes must have a
very significant influence on the optical properties of the stellar
atmospheres. Thus, it is shown that these processes and their importance for
non-local thermodynamic equilibrium (non-LTE) modeling of the solar atmospheres
should be investigated further.
