Structure solution of Co-rich decagonal Al–Co–Ni

Abstract

The structure of Co-rich decagonal Al_72.5Co_18.5Ni₉ has been determined by single crystal X-ray diffraction methods. This is the only modification with four-layer periodicity showing sharp Bragg reflections in all reciprocal space layers. The quasilattice parameters are a_1–4 = 4.464(1) Å and a₅ = 8.137(3) Å; the Laue group is 10/mmm. Structure solution was performed by the 5D ‘charge-flipping method’. Due to pseudosymmetry, only a structure model averaged over a two-layer period (4.068 Å) could be obtained.

Acknowledgement

We thank Lukas Palatinus for his support with SUPERFLIP and gratefully acknowledge financial support under grant SNF 200020-105158.