X-ray photoelectron spectroscopy and magnetism of AlDyNi, AlDyNi4 and AlDy3Ni8 compounds

The electronic and magnetic properties of AlDyNi, AlDyNi4 and AlDy3Ni8 are studied using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), static and dynamic magnetic measurements. The three compounds AlDyNi, AlDyNi4 and AlDy3Ni8 are single phases and crystallize in the Fe2P, CaCu5 and CeNi3 structure types, respectively. All the investigated compounds order ferromagnetically below the corresponding Curie temperatures. The Curie temperature and the magnetic moments are 25 K and 6 μB/f.u. for AlDyNi, 14 K and 6.9 μB/f.u. for AlDyNi4 and 22K and 19.2 μB/f.u. for AlDy3Ni8. At high temperature the magnetic susceptibility obey the Curie-Weiss law. The paramagnetic Curie temperature and the effective magnetic moments are 30K and 10.88 μB/f.u. for AlDyNi, 28 K and 10.94 μB/f.u. for AlDyNi4 and 18 K and 18.33 μB/f.u. for AlDy3Ni8. XPS valence band and Ni 2p spectra indicated the presence of small magnetic moment on Ni sites in AlDy3Ni8 and AlDyNi4, and a complete filling of Ni 3d band in AlDyNi.