Theoretical calculation of characteristic radiation: multiconfiguration Dirac-Hartree-Fock calculations in scandium Kα and Kβ

The characteristic x-ray spectra of 3d transition metals are a constant source of advances in atomic physics, x-ray spectrometry, and quantum mechanics. Prior to this work, there was a discrepancy of 0.549 eV between theoretical and experimental results for the scandium K alpha(1) peak energy, representing a 55 sigma discrepancy using the experimental uncertainty. This work improves this to a 0.330 eV discrepancy with only a 4 sigma error between experiment and theory. Furthermore, we add considerable evidence that asymmetries in x-ray spectra are described by shake events. This work provides ab initio calculations for the diagram and shake-off satellite lines of Sc K alpha and K beta and makes significant improvement on the previous fitting between theory and experiment, from a chi(2)(r) of 7.35 and 20.85 to 1.60 and 1.45 for K alpha and K beta, respectively. Therefore, we make a strong claim that the asymmetries in scandium x-ray lines exist due to satellite lines with very little room for other hypothesised phenomena to exist, such as Kondo-like interactions and Doniac-Sunjic asymmetries. By fitting to the best experimental data for Sc K alpha, beta we obtain values for the width and intensity of the satellite lines which enable us to reconstruct the K alpha, K beta profiles.

Automated summary

The characteristic x-ray spectra of 3d transition metals are analyzed, and the consistency between theoretical and experimental results is improved. Evidence supporting the description of asymmetries in x-ray spectra by shake events is provided. The study reconstructs the spectra of Sc K alpha and K beta through ab initio calculations and fitting of experimental data.