Inverse problems in neutron and x-ray reflectivity studies
We present a new method for obtaining the scattering length density (sld) profile perpendicular to a uniform, smooth surface which is consistent with the measured reflectivity over a finite Q range. The method is applicable to a free liquid surface as well as a thin film deposited on a known substrate. As an illustration, we apply the method to obtain: degree of ordering of an intact Langmuir-Blodgett film on a silicon substrate; surface-induced layering of water and oil in bicontinuous microemulsions; and segregation of polymers near air-film and the film-substrate interfaces.
Key wordsReflectivity Langmuir-Blodgett film microemulsions polymer film
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