119Sn Mössbauer spectroscopy studies of REMn6Sn6 compounds (RE=Sc, Y, Tb-Tm, Lu)

The ternary compounds REMn6Sn6 compounds (RE=Sc, Y, Tb-Tm, Lu) have been examined by 119Sn Mössbauer spectroscopy. The evolution of the transferred hyperfine fields at the three tin sites has been analyzed. The occurrence of isotropic and anisotropic contributions of both the Mn and RE moments is demonstrated. The large variation of the RE atomic size makes evidence of a volume dependence on the hyperfine field transfer constants. The evolution of the hyperfine field in different kinds of magnetic structures suggests a minor contribution of the next-nearest magnetic neighbours. The main magnetic characteristics of the REMn6Sn6 compounds observed by neutron diffraction such as the temperature dependent moment reorientations or the thermal variation of the propagation vector component are in full agreement with the measured 119Sn hyperfine parameters.