An Implicit-Solvent Model for the Interfacial Configuration of Colloidal Nanoparticles and Application to the Self-Assembly of Truncated Cubes

• Published in: Journal of chemical theory and computation Vol. 16; no. 9; pp. 5866 - 5875
• Main Authors: Gupta, U, Escobedo, F. A
• Format: Journal Article
• Language: English
• Published: Washington American Chemical Society 08.09.2020
• Subjects: Computer simulation; Condensed Matter, Interfaces, and Materials; Configurations; Constraint modelling; Cubes; Lattices; Nanoparticles; Quaternions; Self-assembly; Solvents
• ISSN: 1549-9618; 1549-9626
• DOI: 10.1021/acs.jctc.0c00283

This study outlines the development of an implicit-solvent model that reproduces the behavior of colloidal nanoparticles at a fluid–fluid interface. The center point of this formulation is the generalized quaternion-based orientational constraint (QOCO) method. The model captures three major energetic characteristics that define the nanoparticle configurationposition (orthogonal to the interfacial plane), orientation, and inter-nanoparticle interaction. The framework encodes physically relevant parameters that provide an intuitive means to simulate a broad spectrum of interfacial conditions. Results show that for a wide range of shapes, our model is able to replicate the behavior of an isolated nanoparticle at an explicit fluid–fluid interface, both qualitatively and often nearly quantitatively. Furthermore, the family of truncated cubes is used as a test bed to analyze the effect of changes in the degree of truncation on the potential-of-mean-force landscape. Finally, our results for the self-assembly of an array of cuboctahedra provide corroboration to the experimentally observed honeycomb and square lattices.