Shake-up satellites in X-ray photoelectron spectroscopy

Shake-up satellite peaks have been reported in the core electron spectra of various types of molecules. The specific valence excitation(s) giving rise to this extra structure has been assigned largely as a result of the application of the sudden approximation coupled with other considerations, e.g. transition energies. Satellite peaks appearing in the core electron spectra of first row transition metal complexes appear to be particularly interesting since existing data indicate that their positions and intensities convey information regarding some important properties of the complex. In this work reported shake-up satellite peaks are described and analyzed. In addition, some areas requiring more experimental work are pointed out, and a few potential applications of satellite peak data are mentioned.