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Effective interactions between star polymers

Hsiao-Ping Hsu·Peter Grassberger
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Abstract

We study numerically the effective pair potential between star polymers with equal arm lengths and equal number $f$ of arms. The simulations were done for the soft core Domb-Joyce model on the simple cubic lattice, to minimize corrections to scaling and to allow for an unlimited number of arms. For the sampling, we used the pruned-enriched Rosenbluth method (PERM). We find that the potential is much less soft than claimed in previous papers, in particular for $f\gg 1$. While we verify the logarithmic divergence of $V(r)$, with $r$ being the distance between the two cores, predicted by Witten and Pincus, we find for $f>20$ that the Mayer function is hardly distinguishable from that for a Gaussian potential.

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Hsiao-Ping Hsu, Peter Grassberger. 2004-07-07. Effective interactions between star polymers. https://doi.org/10.1209/epl%2Fi2004-10040-x

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