On the Fine Structures of X-ray Absorption Spectra of Amorphous Substances The Amorphous State of the Binary System of Nickel-Sulfur. II.

We prepared the simultaneously electrodeposited Ni-S containing O, 9, 13, 17 and 25 wt. % sulfur and studied their crystalline forms and electrical resistances. Of these samples, those containing 9, 13 and 17% sulfur are amorphous and crystallize when heated to 180°C. The above results were reported in paper I. 1) We photographed the fine structures of Ni K X-ray absorption spectra in the amorphous and crystalline states of the same samples. We measured the wave-lengths of the fine structures of the Ni K absorption edge and intensities of their non-absorption maxima. We find the fine structures in the amorphous states; their shapes and wave-lengths show a similarity to those shown by the substances which have undergone crystallization. But generally, in the amorphous state, the fine structure is less pronounced at the shorter wave-length side than in the crystalline state. We conclude from the above results and previous results in paper I that the amorphous Ni-S is the aggregate state of fine crystals, and that the crystal size influences the region of the extended fine structure.