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Rh(20 Å)/57Fe(tFe) multilayers with Fe thicknesses tFe of 2, 5, 10, and 15 Å prepared by alternate evaporation in UHV have been investigated by x-ray diffraction (XRD), Mössbauer spectroscopy, and SQUID magnetometry. First- and second-order superstructure Bragg peaks (but no higher-order peaks) in small-angle XRD patterns suggest some compositional modulation. Mössbauer spectra taken at 4.2 K are characterized by a distribution P(Bhf) of hyperfine fields Bhf. Peaks observed in the P(Bhf) curves near 17 and 35 T are assigned to an fcc-RhFe interface alloy (~7–24 at. % Fe) with spin-glasslike properties and to a disordered ferromagnetic bcc-FeRh alloy (~96 at. % Fe), respectively. The magnetic transition temperature of the fcc alloy was found to be 23 and 45 K for tFe=2 and 5 Å, respectively, and Bhf follows a T3/2 law. For tFe=2 Å, spin-glasslike behavior was observed by magnetometry. Journal of Applied Physics is copyrighted by The American Institute of Physics.