THE FOCUSING MIRROR: NEW POSSIBILITIES FOR TRANSMISSION EXPERIMENTS IN THE POWDER DIFFRACTOMETER

Martijn Fransen and Detlef Beckers

PANalytical, Almelo, The Netherlands

The capillary transmission geometry is generally accepted as the best way for minimizing preferred orientation effects in powder X-ray diffraction experiments, especially when working with organic materials, such as pharmaceutical samples. Normally, focusing incident beam monochromators are used to enhance resolution, or graded multilayer parabolic mirrors to enhance intensity.

Focusing incident beam monochromators are significantly reducing intensities. Multilayer graded parabolic mirrors are converting divergent beam to parallel beam, therefore the instrumental resolution is defined by the diameter of the capillary.

In order to combine both high resolution of focusing beam, and high intensity of graded multilayer optics, a graded multilayer elliptical mirror has been developed. In this presentation, the first results obtained with this geometry are discussed.