Localized Magnetic Moments in Metals

A simple model is used to obtain information about localized magnetic moments in metals from Mössbauer (or nuclear magnetic resonance) experiments. The formulation emphasizes the explicit dependence of the hyperfine field on the spin $S^{\prime }$ of the Fe atom and shows why the temperature dependence of the hyperfine field follows a Brillouin function of the total localized spin $S$ (with $S\ne S^{\prime }$). The moment of Fe atoms in dilute concentrations of Pd, Rh, and Mo are determined and the apparent contradiction between Mössbauer and susceptibility measurements for Rh and Mo is discussed.