Crystallite Size Analysis Using XRD

Crystallite size analysis is an important application in the chemical and pharmaceutical industries. This is because process parameters or material properties are closely related to crystallite size or surface area.

The Bruker D6 PHASER is ideally suited for rapid crystallite size analysis using powder X-ray diffraction. Analysis is based on the evaluation of the diffracted peak profiles. These show a characteristic broadening that increases as the crystallites become smaller. Broadening must be separated from the instrumental line broadening, which determines the upper limit of the crystallite size. The lower limit of the analysis is determined by the ability to separate broad, low intensity signals from the instrumental background.

Key characteristics of the D6 PHASER explored in this application note include:

• Angular resolution better than 0.03° 2Theta
• High X-ray flux, achieved by the 600 W or 1.2 kW generator, the compact goniometer radius, and the motorized divergence slit that illuminates a large and constant sample area at all measurement angles.
• Dynamic Beam Optimization (DBO) provides tight control of the instrument background to enable separation of broad peaks.