Magnetization and specific heat study of metamagnetism in Lu2Fe17-based intermetallic compounds

The effects of substitutions of Ru for Fe and Ce for Lu on magnetic and thermal properties of Lu2Fe17 are studied by means of magnetization and specific heat measurements on single-crystalline samples of Lu2Fe17-xRux (x = 0, 0.5 and 1) and (Lu0.8Ce0.2)2Fe17. It is shown that both substitutions lead to the suppression of the low-temperature ferromagnetic (F) phase present in the initial Lu2Fe17 compound, resulting in stabilization of the antiferromagnetism in the whole range of magnetic order. An increase of the Sommerfeld coefficient γ is found for both substitution cases. The results are discussed taking into account the interatomic distance variation and the change of the electronic structure upon substitution. Thermal properties of (Lu0.8Ce0.2)2Fe17 and Lu2Fe16.5Ru0.5 are also studied across the metamagnetic transition restoring the F coupling.