Electron Diffraction Study of Evaporated Films of Nickel and Cobalt

Abstract

Evaporated films of nickel and cobalt formed on amorphous bases were studied by the radial distribution method of electron diffraction. The mean thickness of films was the order of 10A. Such thin films are not continuous and consist of crystallites with size of the order of 10A. For nickel crystallites, the lattice constant and the amplitude of thermal vibration are the same as those of massive crystals but anomalous neighbours of h.c.p. type are found. These results are the same as those for silver which were studied in the previous work (J. Phys. Soc. Japan 13 (1958) 1015). For cobalt crystallites at room temperature, the amplitude of thermal vibration turns out to be twice as large as that of massive cobalt crystals and the numbers of neighbours are found to be equal to those which are calculated for a mixture of h.c.p. and diamond structures. At high temperatures, cobalt crystallites become to be h.c.p. and gradually transform to f.c.c. structure. The amplitude of thermal vibration is 0.15A at 250°C a...