For many years, powder X-ray diffraction was used primarily as a fingerprinting method for phase identification in the context of molecular organic materials. In the early 1990s, with only a few notable exceptions, structures of even moderate complexity were not solvable from PXRD data alone. Global optimisation methods and highly-modified direct methods have transformed this situation by specifically exploiting some well-known properties of molecular compounds. This chapter will consider some of these properties.
KeywordsGlobal Optimisation Atom Type Cambridge Structural Database Global Optimisation Method Molecular Connectivity
I am especially grateful to the staff of the CCDC in Cambridge, with whom we have explored the applicability to powder diffraction of many of the tools mentioned here.
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