Delocalization of a hole in Auger transition

Delocalization of a hole in an intermediate state or a final state of Auger transition in metal and charge transfer systems is discussed by using a many-body theory. Its effect on the Augerelectron spectral lineshape is discussed in a general manner. As examples, the L23-VV Augerelectron spectra of metallic Fe and Co are discussed. It is shown that the presence of a delocalized valence-hole created by the L2-L3V Coster-Kronig transition still affects the holehole interaction in the final two-hole state in Co but not in metallic Fe. The present theory supports the interpretation of the L23-VV Auger-electron spectrum of metallic Fe by Sarmaʹs group and Weightmanʹs group and that of the L23-VV Auger-photoelectron coincidence spectroscopy (APECS) spectra of Co and Fe by Thurgate and Lund. The possibility that a final state of Auger transition which involves a charge-transfer core-hole screening electron becomes a single-hole-like state, is pointed out.