Theoretical calculation of characteristic radiation: multiconfiguration Dirac–Hartree–Fock calculations in scandium K α and K β

• Published in: Journal of physics. B, Atomic, molecular, and optical physics Atomic, molecular, and optical physics, 2022-04, Vol.55 (7), p.75002
• Main Authors: Dean, J W, Pushkarna, P, Melia, H A, Nguyen, T V B, Chantler, C T
• Format: Article
• Language: English
• Subjects: characteristic; Dirac–Fock; Multiconfiguration; scandium; theoretical calculations
• ISSN: 0953-4075; 1361-6455
• DOI: 10.1088/1361-6455/ac61ed

The characteristic x-ray spectra of 3 d 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 Kα 1 peak energy, representing a 55 σ discrepancy using the experimental uncertainty. This work improves this to a 0.330 eV discrepancy with only a 4 σ 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 Kα and Kβ and makes significant improvement on the previous fitting between theory and experiment, from a χ r 2 of 7.35 and 20.85 to 1.60 and 1.45 for Kα and Kβ , 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 Kα , β we obtain values for the width and intensity of the satellite lines which enable us to reconstruct the Kα , Kβ profiles.