A string reaction coordinate for the folding of a polymer chain

Author(s)
Christian Leitold, Wolfgang Lechner, Christoph Dellago
Abstract

We investigate the crystallization mechanism of a single, flexible homopolymer chain with short range attractions. For a sufficiently narrow attractive well, the system undergoes a first-order like freezing transition from an expanded disordered coil to a compact crystalline state. Based on a maximum likelihood analysis of committor values computed for configurations obtained by Wang-Landau sampling, we construct a non-linear string reaction coordinate for the coil-to-crystal transition. In contrast to a linear reaction coordinate, the string reaction coordinate captures the effect of different degrees of freedom controlling different stages of the transition. Our analysis indicates that a combination of the energy and the global crystallinity parameter Q(6) provide the most accurate measure for the progress of the transition. While the crystallinity paramter Q(6) is most relevant in the initial stages of the crystallization, the later stages are dominated by a decrease in the potential energy.

Organisation(s)
Computational and Soft Matter Physics
External organisation(s)
Österreichische Akademie der Wissenschaften (ÖAW), Leopold-Franzens-Universität Innsbruck
Journal
Journal of Physics: Condensed Matter
Volume
27
No. of pages
6
ISSN
0953-8984
DOI
https://doi.org/10.1088/0953-8984/27/19/194126
Publication date
05-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
103036 Theoretical physics, 103015 Condensed matter, 103029 Statistical physics
Keywords
ASJC Scopus subject areas
Condensed Matter Physics, General Materials Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/14c0bb59-b163-44f7-81c2-4dafd6cdcb59