Abstract
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.
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Notes
- 1.
Carrying such calculations to their logical periodic conclusion brings us to the domain of crystal structure prediction.
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Acknowledgements
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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© 2012 Springer Science+Business Media Dordrecht
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Shankland, K. (2012). Organic Compounds. In: Kolb, U., Shankland, K., Meshi, L., Avilov, A., David, W. (eds) Uniting Electron Crystallography and Powder Diffraction. NATO Science for Peace and Security Series B: Physics and Biophysics. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-5580-2_5
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