Substitution studies of Mn and Fe in Ln6W4Al43 (Ln=Gd, Yb) and the structure of Yb6Ti4Al43

The synthesis and characterization of Mn- and Fe-substituted Ln6W4Al43 (Ln=Gd, Yb) and Yb6Ti4Al43 are reported. The compounds adopt the Ho6Mo4Al43 structure type with lattice parameters of a~11Å and c~17.8Å with structural site preferences for Mn and Fe. The magnetization of Yb6W4Al43 is sensitive to Mn and Fe doping, which is evident by an increase in the field dependent magnetization. Gd6W4Al43, Gd6W4Al42.31(11)Mn0.69(11), and Gd6W4Al41.69(12)Fe1.30(12) order antiferromagnetically in the ab- and c-directions at 15, 14, and 13K, respectively, with positive Weiss constants, suggesting the presence of ferromagnetic exchange interactions. Anisotropic magnetization data of Gd6W4Al43−yTy (T=Mn, Fe) analogs are discussed. The magnetic susceptibility of Ln6W4−xAl43−yTx+y (Ln = Gd, Yb; T= Mn, Fe). [Display omitted] •Single crystals of Ln6W4−xAl43−yTx+y were grown with Al-flux.•Anisotropic magnetic behavior were determined on single crystals.•Gd6W4−xAl43−yTx+y (T=Mn, Fe) analogs order antiferromagnetically.