Quasicrystalline d-AlCuCo identified as random tiling by ion channeling combined with particle-induced X-ray emission

In a model quasicrystal for decagonal AlCuCo the phason disorder was gradua lly increased and the channeling particle-induced x-ray emission (PIXE) yie lds were computed for 3 MeV He ions by Monte Carlo simulations. For large p hason disorder good agreement with experimental data was obtained. Thus we conclude that the sample of d-AlCuCo used in the measurements is a random t iling. One remaining discrepancy, namely, that the PIXE yields of the simul ations are approximately the same for Cu and Co, is eliminated by optimizat ion of the Cu and Co positions.