Photoemission and Optical Studies of Cu–Ni and Ag–Mn Alloys

Abstract

Photoemission and optical studies of transition metals alloyed into noble metals enable us to distinguish between the rigid band model for these alloys and models such as that of the virtual bound state in which the local nature of the transition‐metal d state is retained. For the noble‐metal‐rich Cu–Ni and Ag–Mn alloys we have studied, the results are in agreement with the virtual bound state model. For both systems, no change is observed in the energy separation between the top of the noble‐metal d band and the Fermi level. With the addition of Ni to Cu, states are formed above the Cu d states which extend to the Fermi level. For 7–14% Mn in Ag the filled Mn d states do not extend to the Fermi level, rather they are separated from it by about 1.5 eV. The width at half‐maximum of the virtual bound states is estimated to be about 1.5 eV for Ni in Cu and about 2 eV for Mn in Ag.