Comparison of Intensities from Fixed and Variable Divergence X-Ray Diffraction Experiments

Diffracted intensities from an X-ray diffractometer operating with fixed or variable divergence slits were compared, following a reported systematic deviation from the theoretical 1/sin θ intensity ratio between these two slit configurations. The theoretical relationship was found to hold over a wide 2 θ range provided the anti-scatter slit did not obstruct the beam at higher diffraction angles as the variable slit increased beam divergence. Such obstruction was found to be a possible explanation for the reported deviation.