119Sn Mössbauer effect study of DyxFe6Sn6 (x = 0.3, 0.5, 1) compounds

119Sn Mössbauer spectroscopy was performed on DyFe6Sn6, crystallizing in a superstructure of the HfFe6Ge6-type, Cmcm, and DyxFe6Sn6 (x = 0.3, 0.5), defect isotypes of the SmMn6Sn6-type structure, P6/mmm. The Fe sublattice orders well above room temperature while in the x = 1 and 0.5 compounds the Dy sublattice orders below 11 and 5.4 K, respectively. Referring all the data to the crystallographic settings of the SmMn6Sn6-type structure, a single transferred hyperfine field Btransf is observed on Sn on 2e sites in DyFe6Sn6, while three different Btransf are detected on 2e sites in DyxFe6Sn6 (x < 1) with magnitudes decreasing with the number of Dy near neighbours. Sn on 2c and 2d sites have no Btransf from the Fe sublattice. However a non-zero Btransf from Dy atoms is observed in x = 1 and 0.5 compounds, confirming the magnetic ordering of the rare-earth sublattice.