Thermal Fluctuations in a Lamellar Phase of a Binary Amphiphile-Solvent Mixture: A Molecular Dynamics Study

Abstract

We investigate thermal fluctuations in a smectic A phase of an amphiphile-solvent mixture with molecular dynamics simulations. We use an idealized model system, where solvent particles are represented by simple beads, and amphiphiles by bead-and-spring tetramers. At a solvent bead fraction of 20 % and sufficiently low temperature, the amphiphiles self-assemble into a highly oriented lamellar phase. Our study aims at comparing the structure of this phase with the predictions of the elastic theory of thermally fluctuating fluid membrane stacks [Lei et al., J. Phys. II 5, 1155 (1995)]. We suggest a method which permits to calculate the bending rigidity and compressibility modulus of the lamellar stack from the simulation data. The simulation results are in reasonable agreement with the theory.

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• New mechanism of membrane fusion
• Optimized Constant Pressure Stochastic Dynamics
• Monte Carlo simulations of copolymers at homopolymer interfaces: Interfacial structure as a function of the copolymer density

Cited by in corpus (6)

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• Pores in Bilayer Membranes of Amphiphilic Molecules: Coarse-Grained Molecular Dynamics Simulations Compared with Simple Mesoscopic Models
• Are stress-free membranes really 'tensionless'?
• Formation and structure of the microemulsion phase in two-dimensional ternary AB+A+B polymeric emulsions
• Fluctuations and Defects in Lamellar Stacks of Amphiphilic Bilayers