ALCHEMI study of an Al₇₂Ni₂₀Co₈ decagonal quasicrystal

Abstract

Electron channeling patterns, which record the intensity variation of characteristic X-ray emission as a function of the incident direction of an electron beam, have been taken from an Al₇₂Ni₂₀Co₈ decagonal quasicrystal for the first time. The channeling patterns show that Al atoms and transition metals occupy respectively different lattice sites, but that both of Ni and Co atoms occupy in disorder the same lattice sites. This supports that the alloy is an electron compound, where the composition of Ni and Co adjusts the value of the electron atom ratio of the alloy.