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Rotational dynamics and friction in double-walled carbon nanotubes

J. Servantie·P. Gaspard
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Abstract

We report a study of the rotational dynamics in double-walled nanotubes using molecular dynamics simulations and a simple analytical model reproducing very well the observations. We show that the dynamic friction is linear in the angular velocity for a wide range of values. The molecular dynamics simulations show that for large enough systems the relaxation time takes a constant value depending only on the interlayer spacing and temperature. Moreover, the friction force increases linearly with contact area, and the relaxation time decreases with the temperature with a power law of exponent $-1.53 \pm 0.04$.

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J. Servantie, P. Gaspard. 2006-06-09. Rotational dynamics and friction in double-walled carbon nanotubes. https://doi.org/10.1103/physrevb.73.125428

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