CFPHGLF calculation of3S excited states for heliumlike three-body systems

Abstract

The correlation-function potential-harmonic and generalized Laguerre function method Ž . CFPHGLF proposed recently by us is used to directly solve the Schrodinger equations 3 Ž . of low-lying triplet states n S n s 2᎐5 for a set of heliumlike systems, including He, Li q , and Be 2q. The eigenenergies converge fast and steadily with potential harmonics Ž .Ž . PH and generalized Laguerre functions GLF . With 10 PH, the percentage errors in the convergent ionization energies for 2 3 S, 3 3 S, 4 3 S, and 5 3 S states of the helium atom are 0.548, 0.291, 0.247, and 0.265% relative to the Hylleraas CI variational values. Somewhat better precision is achieved for Li q and Be 2q systems.