Zinc K β ab initio diagram and satellite transitions

Abstract Anomalies in the characteristic x-ray spectra of 3 d transition metals, particularly in lineshape, linewidth, and intensity ratios, have long motivated detailed investigation. We present the first accurate ab initio study of the zinc K β spectrum, using multiconfiguration Dirac–Hartree–Fock. We predict the zinc K β spectrum, including the K β 1 , 3 diagram doublet together with the dominant satellite transition manifolds for the first time, from [ 4 s ] , [ 3 d ] , [ 3 p ] , and [ 3 s ] single shake-off, as well as [ 3 d 2 ] double shake-off. Such features cannot be resolved by experiment as proven by the literature over several decades. We investigate two novel active space approaches. New convergence metrics are questioned and assessed for energy eigenvalues, gauge ratios A L / A V , transition A coefficients, and a newly developed Σ metric. We achieve energy eigenvalue convergence within 0.03 eV, gauge ratios A L / A V within 0.6%, convergence of transition A coefficients within 0.03% to 0.23%, and convergence of the Σ-metric to within 0.1% to 6.1%. Ab initio shake probabilities are used to quantify satellite contributions to experiment for the first time for zinc. Sequential inclusion of satellite components was evaluated in comparison with the most accurate data available, showing that all dominant shake transitions are required for an accurate description. Incorporating these satellites yields excellent agreement with experiment.