An elementary singularity-free Rotational Brownian Dynamics algorithm for anisotropic particles

Ilie, Ioana M.; Briels, Wim J.; Otter, Wouter K. den,

doi:10.1063/1.4914322

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An elementary singularity-free Rotational Brownian Dynamics algorithm for anisotropic particles

Ilie, Ioana M.·Briels, Wim J.·Otter, Wouter K. den,

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Abstract

Brownian Dynamics is the designated technique to simulate the collective dynamics of colloidal particles suspended in a solution, e.g., the self-assembly of patchy particles. Simulating the rotational dynamics of anisotropic particles by a first-order Langevin equation, however, gives rise to a number of complications, ranging from singularities when using a set of three rotational coordinates to subtle metric and drift corrections. Here, we derive and numerically validate a quaternion-based Rotational Brownian Dynamics algorithm that handles these complications in a simple and elegant way. The extension to hydrodynamic interactions is also discussed.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY ALGORITHMS ANISOTROPY COMPUTERIZED SIMULATION CORRECTIONS LANGEVIN EQUATION METRICS PARTICLES SINGULARITY SOLUTIONS

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Ilie, Ioana M., Briels, Wim J., Otter, Wouter K. den,. 2015-03-21. An elementary singularity-free Rotational Brownian Dynamics algorithm for anisotropic particles. https://doi.org/10.1063/1.4914322

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