Widths of atomic4sand4pvacancy states,46≤Z≤50

Abstract

X-ray photoelectron and Auger spectra involving $N_1$, $N_2$, and $N_3$ vacancy states of Pd, Ag, Cd, In, and Sn were measured and compared with results of free-atom calculations. As previously observed in Cu and Zn Auger spectra that involve $3d$-band electrons, we now also find free-atom characteristics, with regard to widths and structure, in the Ag and Cd $M_4-N_{4,5}{N}_{4,5}$ and $M_5-N_{4,5}{N}_{4,5}$ Auger spectra that arise from transitions of $4d$-band electrons. Theoretical $N_1$ widths computed with calculated free-atom Auger energies agree well with measurements. Theory, however, predicts wider $N_2$ than $N_3$ vacancy states (as observed for Xe), while the measured $N_2$ and $N_3$ widths are nearly equal to each other and to the average of the calculated $N_2$ and $N_3$ widths. The calculations are made difficult by the exceedingly short lifetime of some $4p$ vacancies and by the extreme sensitivity of super-Coster-Kronig rates, which dominate the deexcitation to the transition energy and to the fine details of the atomic potential.