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Separation of the smooth and oscillatory DAFS terms

For an atom in a solid, the total atomic scattering amplitude can be subdivided into smooth and oscillating fine structure components,
The smooth component is given by tex2html_wrap_inline1438, and its smooth anomalous term, tex2html_wrap_inline1440, is usually calculated using the Cromer and Liberman method [18]. The correct values of tex2html_wrap_inline1440, however, are given by embedded atom anomalous amplitudes [19]. For the systems discussed in this chapter, the embedded atom corrections were small, and consequently Cromer-Liberman values were used. When there are neighboring atoms, the oscillating component, tex2html_wrap_inline1444, with the DAFS complex-valued tex2html_wrap_inline1446, contains the spectroscopic and structural information. This separation of f into smooth and oscillatory DAFS components is analogous to the usual XAFS separation of tex2html_wrap_inline1450 into smooth tex2html_wrap_inline1452 and oscillatory tex2html_wrap_inline1454 terms: tex2html_wrap_inline1456.