The excitation of soft X-rays from a single crystal face of nickel

During the progress of our experiments on polycrystalline metals the newly available evidence suggested that crystalline structure might have much to do with the soft X-ray inflections. The fact that the intensity of the inflections was increased by heating the targets to a high temperature by electron bombardment, and that, as had been shown by the experiments of Dr. Nakaya, this same treatment resulted in the formation of a large number of fresh crystal faces on the surface seemed particularly suggestive in this respect. We resolved, therefore, to make experiments on a single crystal surface in the hope that this would result in a simplification of the phenomena. The single crystal used in these experiments was kindly lent to us by Dr. H. H. Potter of the University of Bristol. Nickel crystals are of the face-centred cubic type. The face of the crystal which was used was prepared by Dr. Potter and represented the 100 plane.