AbstractA presentation of fluorescence yields, ωKand ω L 3, in terms of dependence onZis developed from theory, valid for x‐ray excitation by electrons, from literature data and from experiments. The results\documentclass{article}\pagestyle{empty}\begin{document}$$\omega _{\rm K} = 3.3704 \times 10^{ - 1} - 6.0047 \times 10^{ - 2} Z + 3.3133 \times 10^{ - 3} Z^2 - 3.9251 \times 10^{ - 5} Z^3$$\end{document}and\documentclass{article}\pagestyle{empty}\begin{document}$$\omega _{{\rm L}_3 } = 4.4100 \times 10^{ - 2} - 4.7559 \times 10^{ - 3} Z + 1.1494 \times 10^{ - 4} Z^2 - 1.8594 \times 10^{ - 7} Z^3$$\end{document}are a contribution to computer‐supported quantitative x‐r