Electron delocalization and the characterization of theL3MMAuger spectra of3dtransition metals

Abstract

The $L_3{M}_{23}{M}_{23}$, $L_3{M}_{23}{M}_{45}$, and $L_3{M}_{45}{M}_{45}$ Auger spectra of metals with both open and filled $3d$ bands are presented and analyzed in detail. From these experimental data it is possible to derive two parameters, a hole localization parameter ${\lambda }_d$ and an energy parameter $\Delta \epsilon$, which can completely characterize the Auger spectra of the entire $3d$ transition-metal series. ${\lambda }_d$ gives the quantitative extent of the delocalization of the $3d$ electrons in metals with unfilled $3d$ bands. Through a knowledge of ${\lambda }_d$ it becomes possible to quantitatively evaluate the contributions of (i) the hole-hole interaction and (ii) the relaxation, to the total energy difference $\Delta \epsilon$ between single- and double-hole final states. Furthermore these parameters are correlated with the quasiatomic vs band characteristics of Auger electrons.