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arXiv · 1701.00071

Collective Transport of Lennard-Jones Particles through One-Dimensional Periodic Potentials

Abstract

Transport surrounding is full of all kinds of fields, like particle potential, external potential. Under these conditions, how elements work and how position and momentum redistribute in the diffusion? For enriching the Fick law in ordinary, nonequilibrium statistics physics need to be used to disintegrate the complex process. This study attempts to discuss the particle transport in the one-dimensional channel under external potential fields. Two type of potentials, potential well and barrier do not change the potential in total, are built during the diffusion process. There are quite distinct phenomena because of different one-dimensional periodic potentials. We meticulously explore reasons about why external potential field impacts transport by the subsection and statistics method. Besides, one of the evidences of Maxwell velocity distribution is confirmed in assumption of local equilibrium. In addition, we have also investigated the influence of temperature and concentration to the collective diffusion coefficient, by a variety of external force, attaching thermodynamics analyze to these opposite phenomena. So simply is this model that the most valuable point may be an idea, which relating flux to sectional statistics of position and momentum could be referenced in similar transport problems.

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Jian-hui He, Jia-le Wen, Pei-rong Chen, Dong-qin Zheng, Wei-rong Zhong. 2016-12-31. Collective Transport of Lennard-Jones Particles through One-Dimensional Periodic Potentials. https://doi.org/10.1088/1674-1056/26/7/070502

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