Tethered vesicles at constant pressure: Monte Carlo study and scaling analysis

Abstract

Tethered vesicles at various constant pressure differences Δp are investigated by Monte Carlo simulations. Flaccid vesicles (Δp=0) exhibit uncrumpled configurations with a mean-square radius of gyration 〈${\mathit{R}}^2$ ${\mathrm{〉}}_0$∼${\mathit{N}}^{\nu }$, where ν≊1.0 and N is proportional to the surface area. The roughness of their surfaces is characterized by an exponent ζ=0.65. The crossover to inflated vesicles (Δp>0) and to deflated vesicles (Δp<0) are analyzed by means of finite-size crossover scaling assumptions. The crossover to inflated vesicles (ν=1.0) is governed by the reduction of the corrugation due to the pressure, i.e., from ζ=0.65 to 0, which is characterized by a crossover exponent cphi=1.88. The crossover to deflated vesicles is ruled by the change of their sizes, i.e., from ν=1.0 to 0.66, which is characterized by cphi’=4.4.