Comment on “Unconventional enhancement of ferromagnetic interactions in Cd-doped GdFe 2 Zn 20 single crystals studied by ESR and 57 Fe Mössbauer spectroscopies”

Abstract

In the recent publication [Phys. Rev. B 102, 144420 (2020)], Cabrera-Baez et al., present a study of the effects of Cd substitution for Zn in the ferromagnetic compound GdFe2Zn20. As part of this paper they claim that for GdFe2Zn18.6Cd1.4 the effective moment of Gd is reduced by 25%, and the saturated moment of Gd is reduced by over 40%.We regrew representative members of the GdFe2Zn20−xCdx series and did not find any such reductions. In addition, we measured several crystals from the growth batch that was used by Cabrera-Baez et al. and did not see such reductions. Although there is a modest increase in TC with Cd substitution, there is no significant change in the Gd effective moment or the saturated moment associated with the low-temperature ferromagnetic state.