Structural and magnetic characterization of DyFexSn2 (0≤x≤0.3) intermetallics

Powder X-ray diffraction, magnetization and 57Fe Mössbauer spectroscopy measurements are reported for the DyFexSn2 (x=0, 0.05, 0.1, 0.2 and 0.3) series of compounds. Fe enters in the voids of the ZrSi2-type structure of DySn2 giving rise to a CeNiSi2-type structure. At 1000 °C only up to 0.3 Fe atoms per formula unit may be incorporated. These compounds show an antiferromagnetic-like ordering of the Dy sublattice with Néel temperature TN decreasing from 18 K (x=0) down to 7 K (x=0.3). The 57Fe Mössbauer spectra confirms that the Fe is present in a single crystallographic site and shows that the Fe atoms are not magnetically ordered down to 5 K. Although the estimated magnetic effective moments suggest that the Fe magnetic moments are nonzero, the only effect of Fe seems to be a decrease of TN due to the enlargement of the Dy-Dy interatomic distances, as the Fe concentration increases.