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Title: Simulations of stretching a flexible polyelectrolyte with varying charge separation

Abstract

We calculated the force-extension curves for a flexible polyelectrolyte chain with varying charge separations by performing Monte Carlo simulations of a 5000 bead chain using a screened Coulomb interaction. At all charge separations, the force-extension curves exhibit a Pincus-like scaling regime at intermediate forces and a logarithmic regime at large forces. As the charge separation increases, the Pincus regime shifts to a larger range of forces and the logarithmic regime starts are larger forces. We also found that force-extension curve for the corresponding neutral chain has a logarithmic regime. Decreasing the diameter of bead in the neutral chain simulations removed the logarithmic regime, and the force-extension curve tends to the freely jointed chain limit. In conclusion, this result shows that only excluded volume is required for the high force logarithmic regime to occur.

Authors:
 [1];  [2]
  1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
  2. Univ. of California, Santa Barbara, CA (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1326059
Report Number(s):
SAND-2016-3569J
Journal ID: ISSN 1951-6355; 647401
Grant/Contract Number:
AC04-94AL85000
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
European Physical Journal. Special Topics
Additional Journal Information:
Journal Name: European Physical Journal. Special Topics; Journal ID: ISSN 1951-6355
Publisher:
Springer
Country of Publication:
United States
Language:
English
Subject:
97 MATHEMATICS AND COMPUTING

Citation Formats

Stevens, Mark J., and Saleh, Omar A. Simulations of stretching a flexible polyelectrolyte with varying charge separation. United States: N. p., 2016. Web. doi:10.1140/epjst/e2016-60113-0.
Stevens, Mark J., & Saleh, Omar A. Simulations of stretching a flexible polyelectrolyte with varying charge separation. United States. doi:10.1140/epjst/e2016-60113-0.
Stevens, Mark J., and Saleh, Omar A. 2016. "Simulations of stretching a flexible polyelectrolyte with varying charge separation". United States. doi:10.1140/epjst/e2016-60113-0. https://www.osti.gov/servlets/purl/1326059.
@article{osti_1326059,
title = {Simulations of stretching a flexible polyelectrolyte with varying charge separation},
author = {Stevens, Mark J. and Saleh, Omar A.},
abstractNote = {We calculated the force-extension curves for a flexible polyelectrolyte chain with varying charge separations by performing Monte Carlo simulations of a 5000 bead chain using a screened Coulomb interaction. At all charge separations, the force-extension curves exhibit a Pincus-like scaling regime at intermediate forces and a logarithmic regime at large forces. As the charge separation increases, the Pincus regime shifts to a larger range of forces and the logarithmic regime starts are larger forces. We also found that force-extension curve for the corresponding neutral chain has a logarithmic regime. Decreasing the diameter of bead in the neutral chain simulations removed the logarithmic regime, and the force-extension curve tends to the freely jointed chain limit. In conclusion, this result shows that only excluded volume is required for the high force logarithmic regime to occur.},
doi = {10.1140/epjst/e2016-60113-0},
journal = {European Physical Journal. Special Topics},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 7
}

Journal Article:
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