Diffraction Studies of Quasi-Crystals: The Truncation Effects in Six-Dimensions

The Fourier analysis of periodic crystals only needs the Bragg diffraction peaks to elucidate the ideal structure. Aperiodic crystals have a very dense diffraction spectrum of which only the strongest features are actually measured. This introduces specific truncation effects which, in particular, can generate spurious short atomic distances. It is shown that these artifacts are more easily identified and eliminated when the structure is worked out in the associated 6-dim hyperspace.