Efficient tunable generic model for fluid bilayer membranes

Abstract

We present a model for the efficient simulation of generic bilayer membranes. Individual lipids are represented by one head- and two tail-beads. By means of simple pair potentials these robustly self-assemble to a fluid bilayer state over a wide range of parameters, without the need for an explicit solvent. The model shows the expected elastic behavior on large length scales, and its physical properties (eg fluidity or bending stiffness) can be widely tuned via a single parameter. In particular, bending rigidities in the experimentally relevant range are obtained, at least within $3-30 k_{\text{B}}T$. The model is naturally suited to study many physical topics, including self-assembly, fusion, bilayer melting, lipid mixtures, rafts, and protein-bilayer interactions.