M. Dolg et al., A COMBINATION OF QUASI-RELATIVISTIC PSEUDOPOTENTIAL AND LIGAND-FIELD CALCULATIONS FOR LANTHANOID COMPOUNDS, Theoretica Chimica Acta, 85(6), 1993, pp. 441-450
Improved energy-adjusted quasirelativistic pseudopotentials for lantha
noid atoms with fixed valency are presented and tested in molecular ca
lculations for CeO, CeF, EuO, GdO. YbO, and YbF. The pseudopotential c
alculations treat the lanthanoid 4f shell as part of the core and yiel
d accurate estimates for average bond lengths, vibrational frequencies
and dissociation energies of all states belonging to a superconfigura
tion. Information for each individual state of the considered supercon
figuration may be obtained from subsequent ligand field model calculat
ions. The results of this combined pseudopotential and ligand field ap
proach (PPLFT) are compared to more accurate calculations with ab init
io pseudopotentials that include the lanthanoid 4f orbitals explicitly
in the valence shell and to available experimental data.