Magnetic properties of the solid solutions CePt1−x Au x Al (x = 0.1–0.9)

Members of the solid solutions CePt1–x Au x Al have been synthesized from the elements and pure samples could be obtained for the whole range of x from 0.1–0.9. Powder X-ray diffraction patterns indicated the TiNiSi-type structure (orthorhombic, space group Pnma) for the whole series, consistent with the end members CePtAl and CeAuAl. The lattice parameters and therefore also the unit cell volumes evolve in a linear fashion when going from CePtAl to CeAuAl. Magnetic susceptibility and magnetization investigations were performed for the compounds with x = 0.1, 0.2, 0.3, 0.5, 0.7 and 0.9. The results show that the ferromagnetic ground state of CePtAl gets destabilized for small degrees of substitution (x = 0.1) resulting in a lower Curie temperature. For larger values of x, changes towards an antiferromagnetic ground state are observed, in line with pure CeAuAl.