Direct evaluation of the saddle splay modulus of a liquid-liquid interface using the classical mean field lattice model

Abstract

We study the curvature dependence of the liquid-liquid (liquid-gas) interface using the well-known mean field lattice model to estimate its rigidity parameters. The gaussian or saddle-splay modulus is found by evaluating the curvature energy of an interface onto which a saddle shape is imposed as this occurs in an Im3m cubic phase. The resulting values are consistent with those found by the classical indirect route, wherein the gaussian bending modulus results from combining the curvature dependences of the interfacial tension in cylindrical and spherical geometries.