On the monotonicity of the atomic electron momentum density and shell structure of the radial momentum density

Abstract

Numerical investigations on the monotonicity of the electron momentum densities for atoms helium through xenon, using single-zeta and near Hartree–Fock wave functions, have been carried out. It has been noted that, in general, atoms with their ultimate p shells doubly occupied or more tend to show a nonmonotonic electron momentum density. An exception to this is the monotonic behavior exhibited by the elements helium through neon employing single-zeta wave functions. A study of the shell structure in momentum space for the above atoms reveals that all these atoms display, at the most, three maxima in their radial momentum density.