A mazed bicrystal was obtained by vacuum depositing Au onto an [001] Ge substrate. Amongst the various grain boundaries which existed in the bicrystal were facets which were completely asymmetric and exhibited a non-periodic structure. It was shown that specific groups of atoms were present, and their spatial distribution along the boundary plane was analyzed. Diffractograms of experimental high-resolution images revealed the presence of intensity streaks in a non-periodic distribution. The calculated structure of this boundary was in good agreement with the experimentally observed one. A complete analysis of the experimental results led to the conclusion that this boundary represented a one-dimensional quasi-crystal.

High-Resolution Study of a Quasiperiodic Grain Boundary in Gold. J.M.Pénisson, F.Lançon, U.Dahmen: Materials Science Forum, 1999, 294-296, 27-34