Self-assembly of trimer colloids: effect of shape and interaction range

Abstract

Trimers with one attractive bead and two repulsive beads, similar to recently synthesized trimer patchy colloids, were simulated with flat-histogram Monte Carlo methods to obtain the stable self-assembled structures for different shapes and interaction potentials. Extended corresponding states principle was successfully applied to self-assembling systems in order to approximately collapse the results for models with the same shape, but different interaction range. This helps us directly compare simulation results with previous experiment, and good agreement was found between the two. In addition, a variety of self-assembled structures were observed by varying the trimer geometry, including spherical clusters, elongated clusters, monolayers, and spherical shells. In conclusion, our results help to compare simulations and experiments, via extended corresponding states, and we predict the formation of self-assembled structures for trimer shapes that have not been experimentally synthesized.

Molecular dynamics simulation of trimer self-assembly under shear

“…The trimers in this work are qualitatively similar to the recently synthesized patchy colloidal trimers consisting of one smooth and two rough beads, where the smooth beads possess an attractive interaction in the presence of depletant molecules in solution [34]. While these trimers have been the subject of thermodynamic studies [34, 35, 36, 37], there have been no studies on the dynamics of these particles. In addition, the trimer particles geometrically resemble the Y-shape of monoclonal antibodies, and the study of these particles under shear may aid in understanding aggregation-driven increases in the viscosity of monoclonal antibody solutions, with an application of improving the delivery of biological pharmaceuticals [38, 39].…”

FEASST: Free Energy and Advanced Sampling Simulation Toolkit

“…The Free Energy and Advanced Sampling Simulation Toolkit (FEASST) is a free, open-source, modular program to conduct molecular and particle-based simulations with Metropolis, Wang-Landau and Transition-Matrix Monte Carlo methods [1][2][3][4][5][6][7]. FEASST is implemented in C++ and may be imported as a module within Python 2 or 3.…”

Depletion-driven crystallization of cubic colloids sedimented on a surface

“…Quantitative changes may result from the slight change in the depth of the potential well, but these differences may be accounted for by matching the second virial coefficient via extended corresponding states. 42,43 Although the U el term is generally small, it is both a physically meaningful quantity for comparison with experiments and improves transferability of the model to molecular dynamics.…”

“…Second, if the B 22 of the model is well-defined, then extended corresponding-states may be applied to short-range models to directly compare phase behavior between different models and experiment. 42,43,57 Third, comparison of the B 22 for many different tabular potentials is more computationally efficient than comparing between a large set of WL simulations. The size of the table is determined by the following four dimensions: the number of each of the two relative orientations, n θ , the number of scaled separation distances, n z , and the number of values of roundness, n d . See Section III for more details on the definition of the tabular potential.…”

“…Second, if the B 22 of the model is well-defined, then extended corresponding-states may be applied to short-range models to directly compare phase behavior between different models and experiment. 42,43,57 Third, comparison of the B 22 for many different tabular potentials is more computationally efficient than comparing between a large set of WL simulations.…”