MANY DICATIONIC STATES AND 2-HOLE POPULATION ANALYSIS AS A BRIDGE TO AUGER-SPECTRA - STRONG LOCALIZATION PHENOMENA IN BF3

The outer valence double ionization spectrum of BF3 is investigated by computing 100 double ionization transitions with the Green's function method. The results show that one-site and two-site hole localization on the fluorine atoms takes place to full extent and the energy split between clusters of states with similar hole distribution exceeds 10 eV. Double hole localization as a symmetry breaking phenomenon is discussed, pointing out the inherent inability of uncorrelated methods to describe it. A two-hole population analysis of the dicationic states for the quantitative measure of their localized character is presented. The strong effects of hole localization on Auger transition rates are discussed, showing that the two-hole population analysis can be used to develop a new statistical approach to the computation of Auger line shapes. Application of this method to the fluorine and boron KLL Auger spectra of BF3 permits, for the first time, an accurate reproduction of the spectral profiles and a complete interpretation of their features.