Structure of the X-Ray K Absorption Limits of the Elements Manganese to Zinc

The double crystal spectrometer was employed to investigate the main absorption edge of the free elements Mn, Fe, Co, Ni, Cu, and Zn, and the oxides Mn₂{O}₃$, ${Fe}₂O₃, Co₂{O}₃$, ${Ni}₂O₃, CuO, and ZnO. Definite structure was exhibited by all the free elements except Zn, and all the oxides except ZnO. The oxide edges were all displaced toward shorter wave-length. The observed width of the edges varied from 15 volts in the case of Zn to 23 volts for Fe.