The shapes of the Cu $K{\beta }_{2,5}$ lines and Ni $K{\beta }_5$ lines from Cu-Ni alloys vary smoothly with composition. The trend with increasing percentage of the emitting atoms is always toward a flattening out of the peaks of the lines. To explain the observed shapes it has been proposed that the major effect of alloying is a loss of $3d$ band dipole radiation with increasing dilution of the emitting atom. The absorption limits, in contrast to the emission lines, show no influence of alloying. The Cu $K$ limit continues to look like that of pure Cu even when the emitting atom is almost completely surrounded by nickel nearest neighbors, and similarly no changes are observed in the nickel edges even down to 21 percent nickel.

• Received 17 June 1940

DOI:https://doi.org/10.1103/PhysRev.58.400