Configuration mixing in the3s-hole state of transition-metal ions

Results of configuration-interaction calculations for transition-metal ions and for neutral Co and Ni atoms are used to interpret $3s$-photoelectron spectra of transition-metal salts. Only internal configuration with electrons in the $3s$, $3p$, and $3d$ orbitals are included for the ions. For the neutral atoms the $4s$ orbitals are also considered in the internal set. An $N$-electron basis consisting of $L S$-projected determinants is used with a numerical Hartree-Fock orbital basis, obtained from a statistical self-consistent-field (SCF) potential including full exchange. Different sets of occupation numbers have been used to determine the SCF potentials, following ideas of Linderberg and Öhrn. Both observed $3s$ splittings and relative intensities, where available, are adequately estimated by the calculations. Comparisons are also made to much more ambitious calculations, which are available, in some cases, and good agreement is found.