Structural and physical properties of UFe10Mo2

UFe10Mo2 was obtained as single-phase polycrystalline material by annealing at 1450 K a polyphasic sample prepared by melting the elements. This compound was characterized by single-crystal X-ray diffraction, 57Fe Mossbauer spectroscopy and magnetization measurements. UFe10Mo2 was found to crystallize in the space group I4/mmm with cell parameters a=8.4859(3) angstrom, c=4.7508(2) angstrom, V=342.103(21) angstrom3, Z=2 and a ThMn12-type structure that was solved by single-crystal X-ray diffraction to a final R=0.0345 (wR=0.0372). The Mo atoms are randomly distributed in the 8i positions. Magnetization measurements show a ferromagnetic-like behaviour for T<198 K and, in free powder, a saturation magnetization at low temperature of 8.8 μB per formula unit. Comparison with fixed powder measurements indicates a basal plane type of anisotropy. 57Fe Mossbauer spectra below Tc show a distribution of hyperfine fields from 0 to 20 T. This distribution was analysed considering the different local configurations around each Fe atom and assuming the Fe site distribution deduced from X-ray data.