Physics – Condensed Matter – Soft Condensed Matter
Scientific paper
2006-07-25
Eur. Phys. J. E 21, 33 (2006); Eur. Phys. J. E 25, 223(E) (2008)
Physics
Condensed Matter
Soft Condensed Matter
8 pages
Scientific paper
10.1140/epje/i2006-10041-1
The mean area of a two-dimensional Gaussian ring of $N$ monomers is known to diverge when the ring is subject to a critical pressure differential, $p_c \sim N^{-1}$. In a recent publication [Eur. Phys. J. E 19, 461 (2006)] we have shown that for an inextensible freely jointed ring this divergence turns into a second-order transition from a crumpled state, where the mean area scales as $ \sim N$, to a smooth state with $ \sim N^2$. In the current work we extend these two models to the case where the swelling of the ring is caused by trapped ideal-gas particles. The Gaussian model is solved exactly, and the freely jointed one is treated using a Flory argument, mean-field theory, and Monte Carlo simulations. For fixed number $Q$ of trapped particles the criticality disappears in both models through an unusual mechanism, arising from the absence of an area constraint. In the Gaussian case the ring swells to such a mean area, $ \sim NQ$, that the pressure exerted by the particles is at $p_c$ for any $Q$. In the freely jointed model the mean area is such that the particle pressure is always higher than $p_c$, and $$ consequently follows a single scaling law, $ \sim N^2 f(Q/N)$, for any $Q$. By contrast, when the particles are in contact with a reservoir of fixed chemical potential, the criticality is retained. Thus, the two ensembles are manifestly inequivalent in these systems.
Diamant Haim
Haleva Emir
No associations
LandOfFree
Swelling of two-dimensional polymer rings by trapped particles does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Swelling of two-dimensional polymer rings by trapped particles, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Swelling of two-dimensional polymer rings by trapped particles will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-666028