The structure of a (11•4) twin boundary in the pure  phase was studied by means of high-resolution transmission electron microscopy. Two twin boundaries of this orientation were prepared in the form of diffusion-bonded bicrystals. In another of these specimens, one of the surfaces to be bonded was pre-doped with Al. Two distinct boundary structures (B and C) were identified in this specimen. One of these (C) was also observed in the first specimen. The most common structure (C) exhibited continuous lines of intensity maxima through the boundary whereas, in the other structure (B), these were broken by a parallel translation of the grains. The boundary was then simulated by atomistic relaxation, which also resulted in 2 mechanically stable structures which were similar to B and C. An atomistic structure was estimated by fitting the simulated images to experimental micrographs. The theoretical calculations were consistent with some features of the micrographs (in particular, the 2 translation states which were observed), but significant discrepancies remained.

T.Höche, P.R.Kenway, H.J.Kleebe, M.W.Finnis, M.Rühle: Journal of the Physics and Chemistry of Solids, 1994, 55[10], 1067-82