EXTENDED HARTREE-FOCK CALCULATIONS FOR LI AND LI-LIKE IONS

An extended Hartree-Fock (EHF) calculation is performed for the 1s 22s ground state of Li and Li-like ions for z values from 2 through 9. The EHF wavefunction is a two determinant eigenfunction of S2 and S,. The single-particle orbitals are found by solving the coupled integro-differential equations by an iterative numerical integration technique. The results should be the best for the approximate wavefunction used, since the single-particle orbitals do not rely on a choice of basis functions. The total energy, ionization energy, and hyperfine splitting are calculated and the results are compared with similar previous calculations.