Energy and relativistic correction of the 1sns configuration in helium

Abstract

A Mathematica program is developed to calculate the energy and relativistic correction of helium-like atoms in 1sns configuration. A new set of trial functions for 1sns configuration in helium has been suggested. By virtue of the Rayleigh-Ritz variational method, the non-relativistic energies of 1sns configuration in helium (n=2—5) have been calculated, the relativistic corrections, which include mass correction, one- and two-body Darwin correction and spin-spin contact interaction, have been further calculated with the theory of perturbation. The calculated results are in good agreement with experimental data.