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Scaling of Star Polymers with one to 80 Arms

Hsiao-Ping Hsu·Walter Nadler·Peter Grassberger
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Abstract

We present large statistics simulations of 3-dimensional star polymers with up to $f=80$ arms, and with up to 4000 monomers per arm for small values of $f$. They were done for the Domb-Joyce model on the simple cubic lattice. This is a model with soft core exclusion which allows multiple occupancy of sites but punishes each same-site pair of monomers with a Boltzmann factor $v<1$. We use this to allow all arms to be attached at the central site, and we use the `magic' value $v=0.6$ to minimize corrections to scaling. The simulations are made with a very efficient chain growth algorithm with resampling, PERM, modified to allow simultaneous growth of all arms. This allows us to measure not only the swelling (as observed from the center-to-end distances), but also the partition sum. The latter gives very precise estimates of the critical exponents $γ_f$. For completeness we made also extensive simulations of linear (unbranched) polymers which give the best estimates for the exponent $γ$.

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Hsiao-Ping Hsu, Walter Nadler, Peter Grassberger. 2004-07-07. Scaling of Star Polymers with one to 80 Arms. https://doi.org/10.1021/ma0355958

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