Magnetism in the R₅T₄Sn₁₀ (R=Ce, Pr, and Nd; T=Rh and Ir) system

Abstract

We report the study of magnetism in a series of compounds of the type R₅T₄Sn₁₀ (R=Ce, Pr, and Nd; T=Rh and Ir) at low temperatures. Magnetization, resistivity, and heat-capacity studies show that the three compounds of the series R₅Rh₄Sn₁₀ undergo magnetic ordering below 10 K. The transition temperatures are 4.4, 5.5, and 7 K for Ce, Pr, and Nd compounds, respectively. There is a sharp anomaly in the heat-capacity and resistivity data of Nd₅Rh₄Sn₁₀ below 6.5 K which we attribute to a first-order magnetic transition. However, susceptibility, resistivity, and heat-capacity studies show that although Ce₅Ir₄Sn₁₀ orders antiferromagnetically below 4.2 K, Pr₅Ir₄Sn₁₀ remains paramagnetic down to 1.5 K. La₅Ir₄Sn₁₀ shows temperature-independent Pauli paramagnetism and does not exhibit superconductivity down to 1.5 K. The results are compared with that of R₅Ir₄Si₁₀ series.