Evaluation Study of Various Standard X-Ray Powder Diffraction Techniques

Two master mixes of two components each were submitted to eleven different X-ray laboratories for purposes of determining the scatter in d-values and intensities of diffraction data to be expected in routine operations. The results obtained on the two master mixes by ten different diffractometers, five different Debye-Scherrer cameras, and two monochromatic focussing cameras are summarized. Reproducibility of d-values and relative intensities is very high for techniques under good adjustments. The general superiority of data from focussing monochromatic cameras compared to the Debye-Scherrer cameras is illustrated, as well as the diversity observed in diffractometer units. Some statistical data are included relating to the uniqueness of powder diffraction data for identifying crystalline substances.