Bicontinuous structures form, amphiphile aggregate structure

In an intermediate concentration range, where the materials cannot decide if the water or the amphiphile aggregate structure should be the continuous matrix, often so-called bicontinuous structures form. In such bicontinuous cubic phases the interfaces have saddle-splay fype sfructures characterized by nonzero negative mean curvature and negative Gaussian curvature. The most common bicontinuous cubic phase is called gyroid... 

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