论文标题
小棕色颗粒的修改的Stokes-Einstein关系
Modified Stokes-Einstein Relation for Small Brownian Particles
论文作者
论文摘要
Stokes-Einstein（SE）关系已被广泛应用于定量描述布朗运动。尽管如此，我们在这里表明，即使对于简单的流体，SE关系也可能不完全适用。也就是说，尽管对于足够大的布朗粒子而言，SE关系可能是一个很好的近似值，但我们发现它会导致较小的布朗尼粒子引起重大误差，并且随着布朗粒子的大小的减小，误差会增加，直到当Brownian粒子的大小与流体分子的大小相当时，直到SE关系完全失败。原因是基于以下事实：动力学和流体动力效应以不同的方式取决于布朗粒子的大小。通过排除对扩散系数的动力学贡献，我们提出了修订后的Stokes-Einstein关系，并表明它显着扩展了适用的范围。
The Stokes-Einstein (SE) relation has been widely applied to quantitatively describe the Brownian motion. Notwithstanding, here we show that even for a simple fluid, the SE relation may not be completely applicable. Namely, although the SE relation could be a good approximation for a large enough Brownian particle, we find that it induces significant error for a smaller Brownian particle, and the error increases with the decrease of the Brownian particle's size, till the SE relation fails completely when the size of Brownian particle is comparable with that of a fluid molecule. The cause is rooted in the fact that the kinetic and the hydrodynamic effects depend on the size of the Brownian particle differently. By excluding the kinetic contribution to the diffusion coefficient, we propose a revised Stokes-Einstein relation and show that it expands significantly the applicable range.
