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arXiv · 0908.4298

Non-gaussian effects in the cage dynamics of polymers

A. Ottochian·C. De Michele·D. Leporini
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Abstract

The correlation between the fast cage dynamics and structural relaxation is investigated in a model polymer system. It is shown that the cage vibration amplitude, as expressed by the Debye-Waller factor, and the relaxation time $τ_α$ collapse on a single universal curve with a simple analytic form when the temperature, the density, the chain length and the monomer-monomer interaction potential are changed. For the physical states with the same $τ_α$ coincidence of the mean-square displacement, the intermediate scattering function and the non-Gaussian parameter is observed in a wide time window spanning from the ballistic regime to the onset of the Rouse dynamics driven by the chain connectivity. The role of the non-Gaussian effects is discussed.

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A. Ottochian, C. De Michele, D. Leporini. 2009-08-28. Non-gaussian effects in the cage dynamics of polymers. https://doi.org/10.1080/14786430802348060

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