Synthesis, Structure, and Magneto-transport of LnNi1-xSb2 (Ln = Y, Gd−Er)

Abstract

Single crystals of the ternary antimonides LnNi1-xSb2 (Ln = Y, Gd−Er; x ∼ 0.4) have been grown from antimony flux. X-ray diffraction experiments reveal that these compounds crystallize in the tetragonal space group P4/nmm (No. 129) with Z = 2. Lattice parameters are a ∼ 4.3 A and c ∼ 9.3 A. Adopting the HfCuSi2 structure type, these compounds are layered and consist of Ln-capped Sb square nets and NiSb4 tetrahedra arranged in an anti-PbO fashion. The LnNi1-xSb2 compounds show antiferromagnetic ordering and field-dependent magnetization data are also presented. Transport measurements indicate metallic behavior and, most interestingly, positive magnetoresistance for each compound, with large positive magnetoresistance [MR(%) = (ρH − ρ0)/ρ0 × 100] above 100% for the Y-, Dy-, and Ho-analogues at 3 K and 9 T.