Problems associated with the measurement of X-ray attenuation coefficients. I. Silicon. Report of the International Union of Crystallography X-ray Attenuation Project

X-ray attenuation coefficient measurements made on single-crystal silicon specimens by participants in the International Union of Crystallography Attenuation Project are presented for the energy range 8-60 ke V. Twelve laboratories using eight different experimental configurations have provided data for analysis. A comparison is made between measurements using the different techniques at those characteristic wavelengths of interest to crystallographers. Comparison of these measurements with available theoretical cross sections suggests that a model in which the thermal diffuse scattering cross section is used instead of the Rayleigh scattering cross section for the calculation of the theoretical total scattering cross section gives better agreement with the experimental values. No basis was found for preferring one of three current theoretical tabulations of photoelectric absorption cross section over the others.