On highly accurate calculations of the excited n1S(L = 0)-states in helium atoms
Department of Chemistry, University of Western Ontario, N6A 5B7 London, Ontario, Canada
Revised: 12 November 2010
Published online: 14 January 2011
The total energies and various bound state properties of the excited 21S(L = 0)-states in two-electron helium atoms, including the , and atoms, are determined to very high numerical accuracy. The convergence of the results obtained for some electron-nuclear and electron-electron expectation values and, in particular, for the electron-nuclear and electron-electron cusp values, is discussed. The field component of the isotope shift and lowest order QED correction are estimated for the 21S(L = 0)-states in the 4He and 3He atoms. We also apply our highly accurate methods to numerical computations of the excited n1S-states (for n = 3 and 4) in two-electron atomic systems.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2011