Fine Structures of X-ray K Absorption Spectra of Nickel in Oxides of Nickel

Abstract

The fine structures of X-ray K absorption spectra of nickel in metallic nickel, NiO, Ni 2 O 3 and NiO 2 ·nH 2 O were photographed by a bent crystal spectrograph. The fine structures of absorption spectra of metallic nickel and NiO agree well with those published by previous authors, but those of Ni 2 O 3 do not coincide with those reported by Hayasi and Cauchois. Also Cauchois' data of Ni 2 O 3 do not coincide with Hayasi's data. This seems to be due to doubtful chemical structures of Ni 2 O 3 and it is supposed that the three specimens used by the three authors might have different chemical structures. The first absorption maxima A are much more pronounced with increasing oxygen proportion and the general features of α, β, C and γ of the absorption spectra of oxides are similar respectively. However, the second small absorption maxima B are less pronounced with increasing oxygen proportion. These facts are expected from Coster and Kiestra's and Cauchois' considerations. It may be considered from the comp...