Auger-Electron Spectroscopy as a Local Probe of Atomic Charge: SiL2,3VV

Auger-electron spectroscopy is shown to measure something quite different from photoemission: the distribution of atomic (as opposed to overlap) charge populations across the valence bands. While matrix-element effects must be considered in $s-p$ band materials, their inclusion in calculations still lead to poor agreement with experiment. Good agreement may be obtained, however, if one divides the electronic charge into atomic and overlap (bonding) LCAO components and notes that the latter does not contribute to the Auger current.