Magnetic scattering inRMn12−xFexalloys

We measured the electrical resistivity of $R{\mathrm{Mn}}_{12-x}{\mathrm{Fe}}_x$ $(R=\mathrm{Y},$ Er) polycrystalline systems with $0<~x<~9$ over a temperature range of 4–400 K. The overall behavior of the resistivity is determined mainly by the transition metal ions. It exhibits an anomalous rise at or just below the Néel temperature $T_N$ in $x\ne 0$ alloys. We show that electron scattering by spin disorder, both substitutional and thermal, in addition to scattering by phonons and impurities, accounts well for the experimental data without invoking the formation of superzone gaps below $T_N.$