REGULARLY BENT NANOCRYSTALS FORMED IN AN AMORPHOUS FILM OF FE2O3

An unusual lattice bending (up to 120 degrees/mu m) has been observed in different thin amorphous films subjected to an electron or a laser beam etc. We will here report about such a transformation in thin film s of amorphous iron oxide (Fe2O3), which were exposed to a strong elec tron beam inside the electron microscope and transformed to concentric annular areas of ''perfect'' and ''imperfect'' crystals. The two diff erent zones are thus crystalline both with a constant internal bending of the lattice (the crystals themselves are not bent). The grain morp hology in the two zones is, however, completely different with quite l arge grains in the ''perfect'' zones and a nanostructure in the ''impe rfect'' zone, where the grains often are crescentlike with their small est dimension being around 20 nm. There is also an internal rotation o f the lattice from [001] to [100] within the grains. (C) 1997 Acta Met allurgica Inc.