We conceived alternative ways for estimating the 10Dq, exploiting
the facilities of the ADF code, which can work with fractional
populations, controllable by input keywords. In the frame of DFT,
the fractional orbital populations are conceptually allowed [40],
with the meaning of an averaging performed on assemblies of Slater
Determinants with integer occupation numbers in a selected
set of ‘‘active orbitals’’. Aside of the regular calculations having
the occupations of frontier orbitals determined by the usual tn
2gemg
LF scheme