Anomalous scattering diffracting power

For the former, i.e., diffraction, structural refinement techniques that wholly address both the crystalline and diffuse portions of the scattering profiles would be a tremendous advance. The latter component will entail heavier reliance on a variety of powerful probes of local structure including nuclear magnetic resonance, scanning tunneling microscopy, anomalous scattering methods, and radial distribution function analysis [21 j. As the number of chemical/structural architectures available continues to increase, determining the fundamental nature of the structure-property relationships will become an ever more important issue. 

In the past 10 years, anomalous dispersion (AD) effects have been used more and more frequently to solve the phase problem. All elements display an AD effect in x-ray diffraction. However, the elements in the first and second row of the periodic table, for example, C, N, O, and so on, have negligible AD effects. For heavier elements, especially when the x-ray wavelength approaches an atomic absorption edge of the element, these AD effects can be very large. The scattering power of an atom exhibiting AD effects is... 

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