Using fluorescence spectroscopy, experimentalists have provided detailed spectra for these processes. The present calculations reproduce the experimental spectra well, and also provide good predictions for the polarization of the fluorescence. Through frame transformation techniques, we can also determine the influence of relativistic effects on the photoionization spectra. The top figure shows a theoretical spectrum obtained with infinite resolution, while the theoretical results in the bottom figure have been convoluted with the experimental resolution. The interactions between the electrons are very significant in complex open-shell atoms and need to be described accurately to predict the atomic spectra reliably.
Theoretical calculations are valuable to identify the observed features in experiment.
The comparison of theory with experiment also facilitates the identification of relativistic effects in the experimental spectra. Ultimately, we hope that these critical tests will lead to an improved theoretical methodology that can be used to describe the nonseparable quantum mechanical behavior of complex many-body systems.