Density functionals and transition-metal atoms.
Density-functional calculations on transition-metal atoms are problematic due to the numerous possible ways, having inequivalent densities, of occupying the d orbitals. The problem is compounded by the issue of real orbitals versus complex orbitals. In this work we systematize the application of density-functional theories to transition-metal atoms using a current-density-dependent functional. For all the single-determinantal angular momentum eigenstates of ground-state terms, we obtain near degeneracy for the energies as we should. Also, we find a simple rule for occupying the real d orbitals that reproduces the energies of the (complex) angular momentum eigenstate results. Thus the long-standing confusion over how to compute transition-metal atom reference energies is resolved.
Johnson
Erin R
ER
Department of Chemistry, Dalhousie University, Halifax, Nova Scotia B3H 4J3, Canada.
Dickson
Ross M
RM
Becke
Axel D
AD