3p excitations of atomic and metallic Fe, Co, Ni and Cu

The photoabsorption of atomic Fe, Co, Ni and Cu has been determined in the energy range from 45 to 90 eV. For Co, Fe and Ni there is a strong asymmetric resonance at the 3p threshold which is attributed to 3p 6 3d n to 3p 5 3d n+1 transitions. These transitions are split by the interaction of the 3p hole with the partly filled 3d shell and the 3p spin-orbit interaction and considerably modified by the interaction with the 3p 6 3d n to 3p 6 3d n-1 epsilon f transitions. The two channels are strongly coupled bia the 'super Coster-Kronig' decay 3p 5 3d n+1 to 3p 6 3d n-1 epsilon f. The dominant absorption band is conserved in the spectra of the metals whereas the rich atomic fine structure at the 3p threshold and approximately 10 eV above is washed out. The 3d shell is filled in Cu and therefore the strong 3p-3d resonance is missing in the spectra of atomic and metallic Cu.