It is well known that lipids can self assemble into membranes, and form a lamellar phase. Experiments with charged lipids[1], have shown the existence of two lamellar phases—due to the interplay between hydration and electrostatics. The experimental system exhibits a phase transition between these two phases. We introduce a surface-ion interaction, and show that this kind of surface interaction may explain the transition. We investigated, both numerically and analytically, this transition.

[1] M. Dubois, Th. Zemb, N. Fuller, R. P. Rand, and V. A. Parsegian, J. Chem. Phys. 108(18), 7855 (1998).