Magnetic Moments of Intermetallic Compounds of Transition and Rare-Earth Elements

Abstract

The effect of adding the rare‐earth elements to cobalt, iron, and nickel has been investigated. Antiferromagnetic coupling was found to exist in the cobalt and iron rare‐earth compounds. The moment per formula unit of the compound Co₅Y is increased when Sm, Pr, and Nd are substituted for yttrium and decreased when Tm, Gd, Tb, Er, Dy, and Ho are substituted. This is explained on the basis that although the spin moments of cobalt and rare earths are coupled antiferromagnetically in these compounds, the orbital moments add to the cobalt moment in the compounds containing Sm, Pr, and Nd, but they subtract from the cobalt moment in the compounds containing Tm, Tb, Er, Dy, and Ho. For the iron compounds investigated, the moment of the compound Fe₄Y was found only to decrease when Tm, Er, Ho, and Dy were substituted for yttrium. The nickel compounds behaved entirely differently from the cobalt and iron compounds since very little or no antiferromagnetic coupling was observed in these compounds.