THE APPLICATION OF OMEGA SCANS FOR THE CHARACTERIZATION OF GRAPHITE-INTERCALATION COMPOUNDS

The broad two-dimensional intensity distribution of 00l reflections of graphite intercalation compounds (GICs), caused mainly by the mosaic spread, was measured for stage 2 CdCl2-graphite and stage 2 PdCl2-graphite by use of the omega-scan technique. For CdCl2-GICs, the profiles of the measured rocking curves were smooth, similar to the curve profiles of other well-known GICs. For the rocking curves of the PdCl2-GICs a rough shape was found, characterized by several local intensity maxima. This profile type was observed for the first time with GICs; this will require a multitude of measurements for the determination of the entire two-dimensional intensity distribution. The exposure to air of first stage FeCl3-GICs results in a phase separation that is recognizable in the reappearance of the graphite 002 reflection. The profile of the rocking curve of this reflection shows a "smoothed" Gaussian shape, in contrast with the "rough" profile of pristine graphite.