Inverse problems in neutron and x-ray reflectivity studies

  • S. H. Chen
  • X. L. Zhou
  • B. L. Carvalho
Conference paper
Part of the Progress in Colloid & Polymer Science book series (PROGCOLLOID, volume 93)


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 words

Reflectivity Langmuir-Blodgett film microemulsions polymer film 


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Copyright information

© Dr. Dietrich Steinkopff Verlag GmbH & Co. KG 1993

Authors and Affiliations

  • S. H. Chen
    • 2
  • X. L. Zhou
    • 2
  • B. L. Carvalho
    • 1
  1. 1.Department of Materials Science and EngineeringMassachusetts Institute of TechnologyCambridgeUSA
  2. 2.Dept. of Nuclear EngineeringMassachusetts Institute of TechnologyCambridgeUSA

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