Extraction and use of correlated integrated intensities with powder diffraction data

The transformation of a powder diffraction profile into a set of correlated integrated intensities allows crystallographic calculations to be performed without modelling raw diffractometer counts. By carrying out this transformation it is possible to preserve the information about peak overlap without needing to retain the multitude of experimental details and description of the peak shape function. An implementation is described which allows problems of significant size to be tackled. Least squares refinement, issues of data quality and the generation and importance of free R -factors are discussed.