Intensity Measurement of Electron Diffraction Ring Patterns by Means of “Gegenfeld” Filter Technique

抄録

The electron diffraction intensities of evaporated gold, silver and aluminium films are measured by the use of “Gegenfeld” filter technique. The result shows that the integrated line widths of the ordinary diffraction rings are much broader than those of filtered rings and the intensities vary not only with wavelength, crystal size and the structure factor but also with the filter potential. The formula obtained experimentally is
I_∞^hkl=I₀^h exp(cS_hklλ′H).
Here, I_∞^hkl and I₀^hkl are the relative integrated intensity ratios of hkl reflections form ordinary and filtered electron diffraction patterns, S_hkl is the structure factor, H the crystal size, c a coefficient, and λ′ is given by λ(1+0.00059⁄λ²)^1⁄2, where λ is the wavelength of the electrons.