X-Ray K Absorption Edges of Alloys. II. Nickel-Cobalt and Nickel-Iron Solid Solutions

Changes taking place in the fine structure of the cobalt K edge in Ni-Co solid solutions indicate a decline in the 3d-4s hole density at cobalt atom sites. Changes in the Ni K edge in the same alloys suggest that the hole density at nickel atoms increases, thus supporting the rigid-band model for these alloys. Significant changes in the Ni K edges of fcc (gamma) Ni-Fe solid solutions suggest that the rigid-band model may be valid for these alloys also. It does not appear to be applicable, however, to bcc (alpha) solid solutions. In both alloy types, the fine structure at the Fe K edge remained unchanged. Good agreement was obtained with magnetic measurements on bcc Ni-Fe alloys.