Magnetism of approximants in the Al–Mn and Al–Pd–Mn systems

Magnetic properties of approximants in the Al–Mn and Al–Pd–Mn systems have been investigated. Whereas most phases are non-magnetic, localized moments are found on a fraction of the Mn atoms in the hexagonal μ-Al4Mn, orthorhombic T-Al73.1Pd5.2Mn21.7 and cubic 1/1-Al68Pd11Mn14Si7 phases. In all these phases we could identify the crystallographic sites occupied by magnetic Mn. Localized moments are associated with a few particular sites. The moment formation is influenced by the sp–d hybridization. These results contribute to clarify the origin of magnetism in quasicrystalline phases.