SIZE OF AN INFLATED VESICLE IN 2 DIMENSIONS

A two-dimensional vesicle of N monomers of diameter a (or a closed, planar, self-avoiding walk of N links) subject to an internal pressure increment p0 is analyzed. In the large-inflation scaling limit xpa2N2/kBT1, the mean area and mean-square radius of gyration vary as p2N2+ with =(1-)/(2-1)=1/2 and +=/(2-1)=3/2, where =3/4 is the self-avoiding-walk size exponent. The results are related to Pincuss expression for the size of a stretched polymer chain. Monte Carlo simulations confirm the behavior and yield the corresponding scaling functions. © 1990 The American Physical Society.