Ferromagnetism in Dilute Solutions of Cobalt in Palladium

Measurements of the magnetic properties of solid solutions of cobalt in palladium show that ferromagnetism exists in solutions as dilute as 0. 1 at. % of cobalt, when the cobalt atoms are about 10 at. diam apart. The ferromagnetic Curie point is established in this alloy by three different methods as 7^. Bohr magneton numbers are determined for the whole series of alloys, and the moment associated with one cobalt atom is found to increase with dilution from 1. 7 Bohr units in pure cobalt to a limit of 9 to 10 units in the greatest dilution. Lattice constants measured at room temperature show the effect of the onset of ferromagnetism at about 10 at. % cobalt. A simple model explains the magnitude and variation of the cobalt moment.