Extended x-ray-absorption fine-structure study of quasicrystalline Al-Mn alloys

Extended x-ray-absorption fine-structure measurements on the Mn K edge of quasicrystalline Al-Mn alloys indicate that the Mn near-neighbor environment consists of Al neighbors with a significantly broader, more asymmetric distribution than in the analogous crystalline compound, ${\mathrm{Al}}_6$Mn. This distribution in the quasicrystal corresponds either to a highly distorted single-site Mn environment or, more likely, to a superposition of a number of inequivalent Mn sites, in contrast to the crystalline phase which has a single Mn environment.