Lüders Anton, Heß Bastian, Nielaba Peter
Statistical and Computational Physics, Department of Physics, University of Konstanz, 78464 Konstanz, Germany.
Institut für Astronomie und Astrophysik, Eberhard Karls Universität Tübingen, 72076 Tübingen, Germany.
J Chem Phys. 2023 Aug 7;159(5). doi: 10.1063/5.0158286.
We study the diffusive behavior of linear trimer particles via numerical calculations. First, we utilize hydrodynamic bead-shell calculations to compute the microscopic diffusion coefficients for different particle aspect ratios. These values are then used to obtain continuous empirical formulas for said coefficients. As an application example for the empirical formulas, we perform Brownian dynamics simulations of monolayers consisting of a linear trimer surrounded by colloidal spheres. Here, we obtain empirical formulas for the corresponding long-time diffusion coefficients of the trimer. By comparing our data for the microscopic and long-time diffusion coefficients with known results for spherocylinders, we find that the diffusive behavior of both particle geometries is approximately identical. Based on this observation, we introduce simplified equations for the microscopic diffusion coefficients that can be used for arbitrary short rods that are spheres at the minimum aspect ratios. The calculated equations for the diffusion coefficients can be applied to various further numerical and experimental studies utilizing linear trimer particles.
我们通过数值计算研究线性三聚体粒子的扩散行为。首先，我们利用流体动力学珠壳计算来计算不同粒子纵横比下的微观扩散系数。然后，这些值被用于获得所述系数的连续经验公式。作为经验公式的一个应用示例，我们对由线性三聚体被胶体球包围组成的单层进行布朗动力学模拟。在这里，我们获得了三聚体相应的长时间扩散系数的经验公式。通过将我们的微观和长时间扩散系数数据与已知的球柱体结果进行比较，我们发现两种粒子几何形状的扩散行为大致相同。基于这一观察结果，我们引入了微观扩散系数的简化方程，这些方程可用于任意短棒，其在最小纵横比时为球体。所计算的扩散系数方程可应用于利用线性三聚体粒子的各种进一步的数值和实验研究。
