  Anderson models, based on quantum chemical studies of the molecule of
U(C_8H_8)_2, are applied to investigate the problem of an U impurity in a
metal. The special point here is that the U 5f-orbitals are divided into two
subsets: an almost completely localized set and a considerably delocalized one.
Due to the crystal field, both localized and delocalized U 5f-orbitals affect
the low-energy physics. A numerical renormalization group study shows that
every fixed point is characterized by a residual local spin and a phase shift.
The latter changes between 0 and \pi/2, which indicates the competition between
two different fixed points. Such a competition between the different local
spins at the fixed points reflects itself in the impurity magnetic
susceptibility at high temperatures. These different features cannot be
obtained if the special characters of U 5f-orbitals are neglected.
