Ab Initio Manganese Kα and Kβ Energy Eigenvalues, Shake-Off Probabilities, Auger Rates, with Convergence Tests.

Area of Science:

• Atomic Physics
• Quantum Chemistry
• Spectroscopy

Background:

• Manganese (Z=25) Kα spectrum is complex due to its five open 3d orbitals.
• The spectrum includes canonical diagram lines and shake-off satellite lines.
• Accurate theoretical models are needed to understand these spectral features.

Purpose of the Study:

• To perform ab initio calculations for the Kα spectrum of manganese.
• To accurately determine energy eigenvalues for diagram and satellite transitions.
• To calculate shake-off probabilities and Auger transition rates for spectral line intensities.

Main Methods:

• Utilized the multiconfiguration Dirac-Hartree-Fock (MCDHF) method.
• Employed the active set approach for generating atomic wavefunctions.
• Calculated over 280,000 independent transition energies and millions of configuration state functions.

Main Results:

• Presented energy eigenvalue spectra for diagram and satellite transitions.
• Achieved highly converged wavefunctions with over 100 million configuration state functions.
• Obtained convergence in transition energies (within 0.06 eV) and shake-off probabilities (within 4.5%).

Conclusions:

• The MCDHF method with an active set approach provides accurate Kα spectra for complex atoms like manganese.
• The calculations successfully characterized both canonical and shake-off satellite transitions.
• High convergence demonstrates the reliability of the computed spectral parameters.