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Short Time Behavior in De Gennes' Reptation Model

Ute Ebert·Artur Baumgärtner·Lothar Schäfer
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Abstract

To establish a standard for the distinction of reptation from other modes of polymer diffusion, we analytically and numerically study the displacement of the central bead of a chain diffusing through an ordered obstacle array for times $t < O(N^2)$. Our theory and simulations agree quantitatively and show that the second moment approaches the $t^{1/4}$ often viewed as signature of reptation only after a very long transient and only for long chains (N > 100). Our analytically solvable model furthermore predicts a very short transient for the fourth moment. This is verified by computer experiment.

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Ute Ebert, Artur Baumgärtner, Lothar Schäfer. 1997-02-21. Short Time Behavior in De Gennes' Reptation Model. https://doi.org/10.1103/physrevlett.78.1592

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