Local Magnetic Moment Associated with an Iron Atom Dissolved in Various Transition Metal Alloys

Abstract

One atomic percent of iron has been dissolved in a series of alloys of the second row transition metals. The alloys have been chosen so as to give closely spaced coverage from zirconium to beyond palladium. For each dilute iron alloy, the susceptibility $\chi$ has been measured from 1.4°K to room temperature. In some members of the series, the susceptibility is essentially temperature independent, while in others the appearance of a local moment is evidenced by a Curie-Weiss dependence of $\chi$ on $T$. A local moment first appears proceeding from Nb to Mo at about ${\left({\mathrm{Nb}}_{0.6}{\mathrm{Mo}}_{0.4}\right)}_{0.99}$ ${\mathrm{Fe}}_{0.01}$ and persists nearly to Re. Disappearing at this point, the moment reappears at ${\left({\mathrm{Ru}}_{0.75}{\mathrm{Rh}}_{0.25}\right)}_{0.99}$ ${\mathrm{Fe}}_{0.01}$ and continues, becoming large in the alloys near Pd. The occurrence of local moments is discussed in terms of the band structure of the alloys and the perturbation introduced by the iron atom. The giant magnetic moments observed near Pd are related to the large susceptibilities of the iron-free alloys in this region.