Finite size atom: The new quasiparticle in the self-consistent Hartree-Fock approximation

It is shown that, in the self-consistent quantum statistical Hartree-Fock approximation, the number of electronic states localized on one nucleus is finite. This result is obtained on the basis of the general electron-nuclear model of matter and provides convergence of the atomic statistical sum and finiteness of the “atom” size. In general approach the characteristic size of the “atom” is a function of density and temperature. However, it is shown, that in a wide range of thermodynamic parameters, for relatively low temperatures, characteristic orbits and electron energy eigenvalues are independent of density and temperature. In this case, the sizes of the orbits are of order of the Bohr radius which is a minimal characteristic size in the system for typical parameters of plasma with atomic states.