4f density-of-states

An additional process deserves attention in the interpretation of Auger spectra, especially if rare earth metals and compounds are considered. The high 4f density of states above the Fermi level in these materials gives rise to resonant transitions 4d 4f (Zimkina et al., 1967 Sugar, 1972), which can decay by autoionization processes. The electrons ejected in such direct recombination... 

Fig. 1. Radial expectation values, , of the lanthanide for the wave functions at the Fermi level. (For Yb and Lu, we used the 4f wave functions at the center of gravity of the 4f density of states). The values are normalized by their Wigner— Seitz radii.

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