Polarization factor for the X-ray powder diffraction method with a single-crystal monochromator

The polarization correction for X-ray diffraction with a single-crystal monochromator was derived by Azaroff [Acta Cryst. (1955), 8, 701-704]. The correction was restricted to the arrangement in which the monochromator is set before the specimen crystal. In this case, the incident X-ray beam is monochromatized first, then projected on the specimen crystal. The inverse arrangement in which the monochromator is set after the specimen crystal is often used in powder diffraction. In this case, the X-ray beam is diffracted by the specimen crystal first, then monochromatized. This paper is an attempt to derive the polarization factor for the latter arrangement of the specimen crystal and the monochromator.