Dynamical density functional theory for dense suspensions of colloidal hard spheres
Dynamical density functional theory for dense suspensions of colloidal hard spheres
复制标题
胶体硬球致密悬浮液的动力密度泛函理论
DOI：
10.1063/1.4935967
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
H. Hansen
中科院分区：
文献类型：
--
作者：
Daniel Stopper;R. Roth;H. Hansen
利用动态密度泛函理论研究了胶体硬球在布朗运动中的结构弛豫。与部分线性化路径相反[Stopper {\em et al.}, Phys。Rev. E {\bf 92}, 022151(2015)]，即对van Hove函数$G(r,t)$的自部分和不同部分使用不同的自由能泛函，我们对这两个分量提出了使用单一泛函的统一描述。为此，自我部分内部的相互作用通过带有淬灭的自我成分的泛函的零维极限被移除。此外，我们利用了硬球悬浮液长时间迁移的理论结果，使其适应于非均匀流体。我们对G（r,t）的计算结果与数值模拟结果非常吻合，即使在致密液相中也是如此。特别是，我们的理论准确地给出了从短时间内的自由扩散到拥挤环境中较慢的长时间扩散的交叉。
We study structural relaxation of colloidal hard spheres undergoing Brownian motion using dynamical density functional theory. Contrary to the partial linearization route [Stopper {\em et al.}, Phys. Rev. E {\bf 92}, 022151 (2015)] which amounts to using different free energy functionals for the self and distinct part of the van Hove function $G(r,t)$, we put forward a unified description employing a single functional for both components. To this end, interactions within the self part are removed via the zero-dimensional limit of the functional with a quenched self component. In addition, we make use of a theoretical result for the long-time mobility in hard-sphere suspensions, which we adapt to the inhomogeneous fluid. Our results for $G(r,t)$ are in excellent agreement with numerical simulations even in the dense liquid phase. In particular, our theory accurately yields the crossover from free diffusion at short times to the slower long-time diffusion in a crowded environment.