Rietveld refinement using Debye-Scherrer film techniques

The advent of modern diffractometers has overcome the old film techniques that were used during the past years. One reason is that computer-controlled diffractometers made available data in a format ready for the analyses, and the intensities obtained do not suffer for non-linear correction and are very much reliable. The Rietveld method also is established on data obtained from Bragg-Brentano diffractometers equipped with scintillation detectors. However recently, a need for speeding up the analyses is growing, and several experiments have been made to use position-sensitive detectors or energy dispersive detectors for data collection. Very little effort has been involved to resume the old film techniques, coupled with microphotometer systems, that can be used potentially as low cost position sensitive detectors. The film method can be easily improved by simple collection strategies and arrangement on the film-scanning side. The Rietveld method has be successfully applied to the data obtained by the Debye-Scherrer film-technique for structure refinement of a corundum and a quartz samples. A comparison with the results obtainable by a standard Bragg-Brentano diffractometer has been made. Another advantage of the present measurement method is that slight preferred orientations can be easily corrected by rotating the capillary sample holder.