I am looking for a way to computationally analyse the interactions between two molecular species (as solute and solvent) in an isotropic mixture using X-ray scattering. Is there a guideline as to how an obtained structure factor, $S(q)$, can be analysed?
As an example, Figure 2 (below) from Structural analysis of ionic liquids with symmetric and asymmetric fluorinated anions shows the $S(q)$ for various ionic liquids and suggests that the dashed vertical line at 2 $Å^{−1}$ is the approximate boundary between intermolecular ($q < 2 Å^{−1}$) and intramolecular ($q > 2 Å^{−1}$) interactions, which is not clearly evident from the article itself.
A radial distribution function (RDF) for a solid-liquid or liquid mixture can be analysed in terms of solvation shells, coordination numbers, etc, so I was hoping there might be a similar way we can analyse structure factors.