ELASTIC-CONSTANTS FROM A MICROSCOPIC MODEL OF BILAYER-MEMBRANE

A simple microscopic model for amphiphilic molecules dissolved in wate r allows us to obtain within the same scheme the molecular structure o f membranes and micelles, the equilibrium thermodynamics for these agg regates and the elastic constants of the membranes. We present a study of vesicles with cylindrical geometry which, joined to previous resul ts for spherical vesicles, gives the saddle-splay modulus and the bend ing rigidity. Finally, the constraint on the exchange of molecules bet ween the inner and the outer monolayers is included in the model, calc ulating the nonlocal bending curvature. (C) 1998 American Institute of Physics. [S0021-9606(98)70830-X].