L-shell Coster-Kronig transition probabilities in Ni, Cu, and Mo measured with synchrotron radiation.

Abstract

A recent technique, based on differential subshell ionization by tuned synchrotron radiation, has been applied to measurements of {ital L}-subshell Coster-Kronig yields of Ni, Cu, and Mo from {ital L}{sub 2} and {ital L}{sub 3} Auger spectra. Results for Ni are {ital f}{sub 23}=0.6+0.2, {ital f}{sub 12}=0.4+0.2, and {ital f}{sub 13}=0.5+0.2; for Cu, {ital f}{sub 23}=0.8+0.1, {ital f}{sub 12}=0.44+0.06, and {ital f}{sub 13}=0.3+0.2; for Mo, {ital f}{sub 23}=0.15+0.02, {ital f}{sub 12}=0.15+0.02, and {ital f}{sub 13}=0.61+0.06. Measured transition probabilities are compared with previously available information. The results are generally consistent with the body of theoretical and experimental data. For Ni and Cu, the present measurements of {ital f}{sub 23} confirm that the {ital L}{sub 2}-{ital L}{sub 3}{ital M4,5} Coster-Kronig channel is accessible in the metals, even though it is energetically cut off in free atoms. Further improvements in synchrotron-radiation sources are likely to make it possible to throw light on several critical questions by means of the present method.