Precise calculation for energy levels of a helium atom in P states

The energy levels of a helium atom in P stares, for parahelium and orthohel ium with both the odd parity and the even parity, are precisely calculated directly from the Schrodinger equation. The rotational degrees of freedom a re separated completely from the internal ones, so that only three internal variables are involved in both the generalized radial functions and equati ons. By making use of the appropriate internal variables, the singularity i n the solutions is removed and the series in calculation converges very fas t. (C) 2001 Elsevier Science B.V. All rights reserved.