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Theory and implementation

This analysis differs from most of the other scattering-related analysis available in nMOLDYN in the sense that it does not use a discrete q-vectors generation but results from a integration over all the q-vectors for a given q-shell. In that context, the static coherent structure factor is defined as:
\begin{displaymath}
S_{\mathrm{coh}}(q) = \sum^{N_{species}}_{I,J \ge I}\sqrt{n_I n_J \omega_{I,\mathrm{coh}}\omega_{J,\mathrm{coh}}} S_{IJ}(q)
\end{displaymath} (4.184)

where $N_{species}$ is the number of selected species, $n_I$, $n_J$ are respectively the number of atoms of species I and J, $\omega_{I,\mathrm{coh}}$ and $\omega_{J,\mathrm{coh}}$ are respectively the weights for species I and J (see Section 4.2.1 for more details) and:
\begin{displaymath}
S_{IJ,\mathrm{coh}} = \delta_{IJ} + \frac{1}{\sqrt{n_In_I}}\...
...}
\frac{sin(qr_{\alpha\beta})}{qr_{\alpha\beta}}\right\rangle
\end{displaymath} (4.185)

where q is the radius of the q-shell under process, and $r_{\alpha\beta}$ is the distance between atoms $\alpha$ and $\beta$. For more detials about SSCSF analysis please refer to Ref. [69]



pellegrini eric 2009-10-06