| Abstract
| - Spontaneous assembly of long chains of nanoparticles (NPs) has been experimentally observed for manydifferent materials including nanocolloids of semiconductors, metal oxides, and metals. While the origin ofdipole moment in various colloids can be different, a universal explanation of chain assembly can be providedby the hypothesis of dipole−dipole attraction of nanocolloids. In this paper, we describe the application ofthe Monte Carlo method for modeling of self-organization of large ensembles of NPs. As the firstapproximation, the Derjaguin−Landau−Verwey−Overbeek (DLVO) theory provides an adequate descriptionof self-organization of several hundreds of NPs. Unlike microscale colloids that served as a classical modelfor DLVO, we used a distance-dependent media dielectric constant. The simulated chains are morphologicallyand geometrically similar to those observed experimentally. This establishes the fundamentally importantability of NPs to self-assemble due to their intrinsic anisotropy. Thermodynamic analysis of Monte Carloresults reveals the role of partial removal of the stabilizer shell in CdTe nanocolloids necessary for reductionof interparticle repulsion. Analysis of the field distribution around short chains demonstrates that the growthof linear agglomerates is kinetically controlled by a high activation barrier for NPs approaching from all ofthe directions except one end of the chain. The presented algorithm can be applied to other interparticleinteractions, such as induced dipoles, which can stimulate chain formation in the absence of permanent dipolemoment. It can also serve as a theoretical foundation for the understanding of the large complex superstructuresforming from anisotropic and anisometric NPs. Monte Carlo simulation of nanoscale dipoles can also beextended to the interactions of NP with proteins, and related biological systems important for a variety ofapplications in medicine.
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