Oscillations scaled density profiles

Another feature seen in the fine-scaled interfacial density profiles is that the crystal layers tend to relax outward into the fluid region, so that the spacing of the peaks in the density oscillations increases. This phenomenon has also been observed in recent and MD simulations of the singlecomponent hard sphere interface, where it appears to be related to the preference of the fluid to order at the interface in a way that is more consistent with a [111] face. 

At relatively low polymer adsorption levels, oscillatory force profiles similar to those observed for micellar solutions are also seen in polyelectrolyte-containing systems. As with micellar structuring, these oscillations originate from an inhomogenous density distribution of polymer (or polymer/surfactant complexes) within the film. Furthermore, the characteristic length-scale of the oscillatory forces indicate that this structuring is controlled by electrostatic interactions. To date, no complete theory describing this phenomenon exists ... 

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