Single-Crystal X-ray Diffraction
Single-crystal X-ray diffraction is an extremely powerful technique to characterize small drug molecules in solid form. It is a mature technique that is becoming ever more automated, and it is increasingly viewed as “routine” in both industry and academia. On this basis, it is arguable how much the average formulation scientist needs to know about the technique: is it necessary to understand the inner workings of the “black box”, or is it sufficient just to trust the results produced by an automated analysis system? This chapter provides a brief outline of the principles, then considers some aspects that, in the author’s opinion, should still be understood to measure crystallographic data effectively and to interpret crystallographic results. The focus is on selected topics that are likely to be most relevant to pharmaceutical solid-form characterization.
KeywordsDiffraction X-ray Single-crystal SXRD Absolute structure
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