The authors study the photoemission (PES) and bremsstrahlung isochromat (BIS) spectra of Mn in Ag to determine the effective Coulomb interaction F0 between the Mn 3d electrons. They show that, due to many-body and multiplet effects together with the large degeneracy of the 3d level, the main peak in PES and the main peak in BIS tend to be moved towards the Fermi energy by hybridization effects. As a result, the experimental separation between these peaks leads to an underestimate of F0 unless these effects are included. For Mn in Ag these effects, however, appear to be insufficient to obtain agreement between experiment and ab initio calculations for F0.
 

Physical Review B, 44 3518-25, 1991.