Pores in Bilayer Membranes of Amphiphilic Molecules: Coarse-Grained Molecular Dynamics Simulations Compared with Simple Mesoscopic Models
arXiv:cond-mat/0501071 · doi:10.1063/1.1752884
Abstract
We investigate pores in fluid membranes by molecular dynamics simulations of an amphiphile-solvent mixture, using a molecular coarse-grained model. The amphiphilic membranes self-assemble into a lamellar stack of amphiphilic bilayers separated by solvent layers. We focus on the particular case of tension less membranes, in which pores spontaneously appear because of thermal fluctuations. Their spatial distribution is similar to that of a random set of repulsive hard discs. The size and shape distribution of individual pores can be described satisfactorily by a simple mesoscopic model, which accounts only for a pore independent core energy and a line tension penalty at the pore edges. In particular, the pores are not circular: their shapes are fractal and have the same characteristics as those of two dimensional ring polymers. Finally, we study the size-fluctuation dynamics of the pores, and compare the time evolution of their contour length to a random walk in a linear potential.
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Cited by in corpus (8)
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- Elastic Properties and Line Tension of Self-Assembled Bilayer Membranes
- Field Theoretic Study of Bilayer Membrane Fusion III: Membranes with Leaves of Different Composition
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- Title Stabilization of Membrane Pores by Packing
- Coarse-grained models of complex fluids at equilibrium and unter shear