Phase relations different atoms anomalous scattering

The determination of absolute configurations in these investigations was based on a qualitative use of the anomalous scattering effects—on simple observations of which of two opposite reflections, hkl or hkl, was the stronger. It is, however, possible in principle to make quantitative use of the differences between Fhkl and Fjm to determine phase angles directly. The difference between Fhkl and depends on the phase relations of the waves from the anomalously scattering atom and from the rest of the molecule when these two waves are nearly in phase,... 

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