Comparison of an Umweganregung pattern, measured on an automatic single-crystal diffractometer, with calculated patterns

The ψ scan of the forbidden 003 reflection of Zn, measured with an automatic single-crystal diffractometer, using Cu Kα radiation, is compared with the calculated and plotted Umweganregung pattern for Cu Kα₁ and Cu Kα₂ radiation. The intensities of the Umweganregung peaks are calculated on the basis of the kinematical theory. When the Lorentz factors for both scans involved in the measurement (the 0 scan and the ψ scan) are taken into account, excellent agreement between measured and calculated intensities is obtained. The width of the Umweganregung peaks can be explained by replacing the reciprocal-lattice points by spheres in reciprocal space.