Measurement of X-ray Pendellösung intensity beats in diffracted white radiation from silicon wafers

Pendellösung intensity beats of white radiation diffracted from parallel-sided single-crystal wafers of silicon were measured by a solid-state detector. After a few corrections, the extremum positions in the beat were measured to evaluate the atomic scattering factors for various reflections. The scattering factor shows a dependence on wavelength, λ, which can be interpreted by the anomalous dispersion term, f', as calculated by Cromer [Acta Cryst. (1965), 18, 17-23]. The obtained values of the atomic scattering factor expressed as linear functions of wavelength are listed with those at λ = 0.5594 Å for comparison with the data so far obtained with Ag Kα₁ and wedge crystals. The values for 111 and 220 reflections in the present experiment, 10.59 and 8.40, were almost the same as Tanemura & Kato's [Acta Cryst. (1972), A28, 69-80], 10.66₄ and 8.46₃, respectively.