Laves $R{\mathrm{Fe}}_2$ compounds, where $R$ is a rare earth, exhibit technologically relevant properties associated with the interplay between their lattice geometry and magnetism. We apply ab initio calculations to explore how magnetic properties of Fe in $R{\mathrm{Fe}}_2$ systems vary with temperature. We found that the ratio between the orbital magnetic moment ${\mu }_{\mathrm{orb}}$ and the spin magnetic moment ${\mu }_{\mathrm{spin}}$ increases with increasing temperature for $\mathrm{Y}{\mathrm{Fe}}_2, \mathrm{Gd}{\mathrm{Fe}}_2, \mathrm{Tb}{\mathrm{Fe}}_2, \mathrm{Dy}{\mathrm{Fe}}_2$, and $\mathrm{Ho}{\mathrm{Fe}}_2$. This increase is significant and it should be experimentally observable by means of x-ray magnetic circular dichroism. We conjecture that the predicted increase of the ${\mu }_{\mathrm{orb}}/{\mu }_{\mathrm{spin}}$ ratio with temperature is linked to the reduction of hybridization between same-spin-channel states of atoms with fluctuating magnetic moments and to the associated increase of their atomic-like character.

• Received 3 August 2022
• Revised 6 October 2022
• Accepted 10 October 2022

DOI:https://doi.org/10.1103/PhysRevB.106.144416