Structure–Property Correlations in the Heterobimetallic 4f/3d Materials Ln2M(TeO3)2(SO4) (Ln = Y, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu; M = Co or Zn)

Eighteen new lanthanide transition metal heterobimetallic compounds, Ln2Co­(TeO3)2(SO4)2 (Ln = Y, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu) and Ln2Zn­(TeO3)2(SO4)2 (Ln = Sm, Gd, Dy, Ho, Er, or Yb), have been prepared. They crystallize in triclinic space group P1̅ with two different structural topologies occurring because of a reduction in the Ln3+ coordination number from eight to seven with the smallest lanthanides, Yb3+ and Lu3+. Magnetic susceptibility studies of compounds with diamagnetic lanthanides and lanthanide-like ions suggest that antiferromagnetic interactions occur between the Co2+ ions. Similarly, the replacement of Co2+ with Zn2+ yields Ln2Zn­(TeO3)2(SO4)2 (Ln = Gd, Dy, Ho, or Er), and these materials allow for the resolution of the nature of the interactions between lanthanide ions. The data suggest that the short-range Ln3+···Ln3+ interactions are ferromagnetic. However, a wide range of ferro- and antiferromagnetic interactions occur between the Ln3+ and the Co2+ cations, with several compounds exhibiting short-range magnetic correlations below 25 K. The results are discussed and contrasted with those recently reported for the related Ln2Cu­(TeO3)2(SO4)2 family.