Orbital and Spin Magnetization in Fe-Co, Fe-Ni, and Ni-Co

The effective electronic orbital contribution $M_0$ and the effective electronic spin contribution $M_s$ to the spontaneous magnetization $M_t$ for binary alloys of Fe, Co, and Ni are determined from Scott's measured magnetomechanical $g^{\prime }$-factors using the relations $\frac{M_0}{M_t}=\frac{(2-g^{\prime })}{g^{\prime }}$ and $\frac{M_s}{M_t}=\frac{2(g^{\prime }-1)}{g^{\prime }}$ where $g^{\prime }$ is assumed to be independent of the strength of the magnetic field and the temperature. It is believed that $\frac{M_0}{M_t}$ has several-fold greater accuracy when determined from the $g^{\prime }$ factors than when determined from ferromagnetic-resonance $g$ factors. In terms of the Bohr magneton ${\mu }_B$, the orbital magnetic moments for the pure elements at 300°K are: for iron, $(0.0918\mathrm{}\pm 0.0033){\mu }_B$ (4.22% of $M_t$); for cobalt, $(0.1472\mathrm{}\pm 0.0034){\mu }_B$ (8.81% of $M_t$); and for nickel, $(0.0508\mathrm{}\pm 0.0012){\mu }_B$ (8.92% of $M_t$). The $M_s$ values for the fcc phases of the alloys agree well with those reported by Meyer and Asch from their $g$-factor data. For these alloys, $M_0$ is much more sensitive to the crystalline structure than $M_s$ and $M_t$ are. The relationship $g^{\prime -1\mathrm{}}+g^{-1\mathrm{}}=1\mathrm{}$ holds for Fe-Ni and Fe-Co alloys (with the exception of one point) within the accuracy of the $g$-factor measurements (∼0.1-1.0%).