Escape transition of a polymer chain from a nanotube: how to avoid spurious results by use of the force-biased pruned-enriched Rosenbluth algorithm

Physics – Condensed Matter – Soft Condensed Matter

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

10 pages, 17 figures

Scientific paper

10.1103/PhysRevE.78.041803

A polymer chain containing $N$ monomers confined in a finite cylindrical tube of diameter $D$ grafted at a distance $L$ from the open end of the tube may undergo a rather abrupt transition, where part of the chain escapes from the tube to form a "crown-like" coil outside of the tube. When this problem is studied by Monte Carlo simulation of self-avoiding walks on the simple cubic lattice applying a cylindrical confinement and using the standard pruned-enriched Rosenbluth method (PERM), one obtains spurious results, however: with increasing chain length the transition gets weaker and weaker, due to insufficient sampling of the "escaped" states, as a detailed analysis shows. In order to solve this problem, a new variant of a biased sequential sampling algorithm with re-sampling is proposed, force-biased PERM: the difficulty of sampling both phases in the region of the first order transition with the correct weights is treated by applying a force at the free end pulling it out of the tube. Different strengths of this force need to be used and reweighting techniques are applied. Using rather long chains (up to N=18000) and wide tubes (up to D=29 lattice spacings), the free energy of the chain, its end-to-end distance, the number of "imprisoned" monomers can be estimated, as well as the order parameter and its distribution. It is suggested that this new algorithm should be useful for other problems involving state changes of polymers, where the different states belong to rather disjunct "valleys" in the phase space of the system.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Escape transition of a polymer chain from a nanotube: how to avoid spurious results by use of the force-biased pruned-enriched Rosenbluth algorithm 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 Escape transition of a polymer chain from a nanotube: how to avoid spurious results by use of the force-biased pruned-enriched Rosenbluth algorithm, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Escape transition of a polymer chain from a nanotube: how to avoid spurious results by use of the force-biased pruned-enriched Rosenbluth algorithm will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-492959

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.