Because of the large degeneracy, Nf, the Anderson model of Ce compounds shows an important asymmetry between f0 and f2 configurations. The valence photoemission spectrum depends strongly on the f2 weight. The spectrum can have a pronounced two-peak structure, with one peak close the f-level energy and a second structure closer to, but possibly below, the Fermi energy.
 

Journal of Magnetism and Magnetic Materials, 47-48 266-8, 1985.