M4,5N4,5XAuger electron spectra of free silver atoms

Abstract

The first high-resolution ${M}_{4,5}{N}_{4,5}{N}_{4,5}$ and ${M}_{4,5}{N}_{4,5}{O}_{1}$ Auger electron spectra from silver vapor have been measured using electron-beam excitation. The spectra reveal fine structure not observable in solid-state measurements. The spectra have been analyzed in terms of the optically known energy levels of the $4{d}^{8}5s$ and $4{d}^{9}$ final-state configurations. The intensity anomaly of the high-energy components of the ${M}_{5}{N}_{4,5}{N}_{4,5}$ group found in the spectrum of solid silver does not exist in the present vapor-phase spectrum. The relative intensities of lines are found to correspond very well to the intensities of $4{d}^{8}$ parent Auger lines calculated in a mixed coupling scheme. For the binding energies of the ${M}_{4}$ and ${M}_{5}$ levels of free silver atoms 381.55 \ifmmode\pm\else\textpm\fi{} 0.10 and 375.55 \ifmmode\pm\else\textpm\fi{} 0.10 eV, respectively, have been obtained. A comparison with the published solid-state photoenergies and Auger energies shows that the free atom binding energies are 3.3 \ifmmode\pm\else\textpm\fi{} 0.5 eV higher and the kinetic energies of the ${M}_{4,5}{N}_{4,5}{N}_{4,5}$ Auger electrons 12.1 \ifmmode\pm\else\textpm\fi{} 0.5 eV lower than the corresponding solid-state values.