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Dysprosium disilicide can form nanowires and three dimensional (3D) islands on the Si(001) surface. The nanowire density and width are metal coverage dependent. Various superstructures are observed on the nanowires. The Si substrate is also reconstructed in either 2×4 or 2×7 superstructures. The nanowires have a minimum height of about 0.5 nm with respect to the Si surface; and the heights of the additional layers growing atop nanowires are quantized, consistent with the hexagonal AlB2 type silicide structure. Longer annealing time and higher coverage promote 3D island growth.

Tilt boundaries have been observed on the (0001) surface of graphite by scanning tunneling microscopy (STM). Rotation angles about the c axis of 6.5°, 8°, and 19° were found, indicating no preferential orientation of grains in the basal plane of graphite. The grain boundary region between crystallites appears disordered with a width varying between 10 and 100 Å. Moiré patterns are observed near grain boundaries when multiple tips scanning over different grains contribute to the image simultaneously. Such images support the theory that multiple isolated tips, occasionally hundreds of angstroms apart, can contribute to STM images.

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