We report on the electrical resistivity and magnetic susceptibility of La or Gd doped RCrSb 3 ͑R = La, Pr, Sm, and Gd͒. Single crystals were grown by increasing the nominal dopant by 25%. In general, two magnetic ordering transitions are found, T c1 is attributed to ferromagnetic ordering of the itinerant Cr sublattice, and, at lower temperatures, T c2 is attributed to ordering of the localized rare-earth sublattice. Alloying on the rare-earth site varies the de Gennes factor, DG= ͑g −1͒ 2 J͑J

more »

... 1͒, and dT c1 / d͑DG͒ = −2 K, while dT c2 / d͑DG͒ = 5 K. These ordering temperatures are found to converge at GdCrSb 3 , where a single ferrimagnetic transition is found at T c2 = 86 K due to an antialignment of the itinerant Cr magnetic sublattice and the localized rare-earth magnetic sublattice. Initially, for DGϽ 3.5, the two magnetic sublattices order in a ferromagnetic ground state, and the paramagnetic Weiss temperature decreases at the same rate as T c1 . But for DGϾ 4.5, the rare-earth magnetic sublattice antialigns with respect to the Cr sublattice, and the Weiss temperature decreases five times as fast. In the region between ͑3.5Ͻ DGϽ 4.5͒, a first-order phase transition is found at T c2 .