Structure and Physical Properties of Ternary Antimonide YbCrSb3

The ternary rare-earth antimonide YbCrSb3 was prepared by arc-melting of the elements. Its structure was determined by single-crystal X-ray diffraction (Pearson symbol oP20, orthorhombic, space group Pbcm, Z = 4, a = 12.981(3) Å, b = 6.140(1) Å, c = 5.993(1) Å). YbCrSb3 is isostructural to LaCrSb3 and CeCrSb3, and extends the RECrSb3 series (previously known for RE = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy) to the latest rare-earth member yet and to one that is essentially divalent instead of trivalent. Electrical resistivity measurements on single crystals and magnetic susceptibility measurements on powders revealed a magnetic ordering transition at T C = ∼280 K, the highest observed so far in the RECrSb3 series. The isothermal magnetization at 100 K indicated an approach to saturation, but with low values (0.08 μB/mol at 9 T). These results suggest a ferromagnetic or canted antiferromagnetic structure.