Bicontinuous Morphologies


The theory and analysis of SANS from BICONTINOUS MORPHOLOGIES is a major research interest in the NIST Center for Neutron Research The LEVELED WAVE MODEL has been developed to describe the geometry of such structures and calculate the scattering from them.
  • Scattering Properties of the Leveled-Wave Model of Random Morphologies
    N. F. Berk, Phys. Rev. A44, 5069 (1991).

    The LWM is described and extended. It is shown how fractal roughness can be incorporated into the model.

  • Scattering Properties of a Model Bicontinuous Structure with a Well Defined Length Scale
    N. F. Berk, Phys. Rev. Lett.,5821, 2718 (1987).

    The leveled wave model is introduced. Its relationship to Cahn's original construction is discussed. It is shown that the model can produce a single Bragg peak at the characteristic wavenumber of the structure. The theoretical behavior of the characteristic peak with scattering contrast variation is shown.

    The characteristic peak vanishes when the only contrast is between the surfactant film and the bulk, with equal volume fractions on either side of the film, as observed in scattering from micromulsions.

  • Structure of a Triglyceride Micremulsion: A Small Angle Neutron Scattering Study
    S. F. Trevino, R. Joubran, N. Parris, and N. F. Berk, Langmuir, 10, 2547 (1994).

    The LWM is applied to SANS from a novel microemulsion.

    More recent work in progess has revealed limitations of the current form of the LWM in this system, in which the two sides of the surfactant phase have very different morphologies.

  • Analysis of SANS from Controlled Pore Glasses
    N. F. Berk, C. J. Glinka, W. HAller, and L. C. Sander, Meter. Res. Soc. Symp. Proc.166, 409 (1990).

    The LWM is applied to controlled pore glasses, and the pore size distribution is discussed.



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Last modified: September 30, 1997