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arXiv · 1708.02195

A Unified Description of Colloidal Thermophoresis

Jerome Burelbach·Daan Frenkel·Ignacio Pagonabarraga·Erika Eiser
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Abstract

We use the dynamic length and time scale separation in suspensions to formulate a general description of colloidal thermophoresis. Our approach allows an unambiguous definition of separate contributions to the colloidal flux and clarifies the physical mechanisms behind non-equilibrium motion of colloids. In particular, we derive an expression for the interfacial force density that drives single-particle thermophoresis in non-ideal fluids. The issuing relations for the transport coefficients explicitly show that interfacial thermophoresis has a hydrodynamic character that cannot be explained by a purely thermodynamic consideration. Our treatment generalises the results from other existing approaches, giving them a clear interpretation within the framework of non-equilibrium thermodynamics.

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Jerome Burelbach, Daan Frenkel, Ignacio Pagonabarraga, Erika Eiser. 2017-12-16. A Unified Description of Colloidal Thermophoresis. https://arxiv.org/abs/1708.02195

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