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arXiv · 1504.07603

Self-Assembly and Waterlike Anomalies in Janus Nanoparticles

José Rafael Bordin·Leandro B. Krott·Marcia C. Barbosa
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Abstract

We explore the pressure versus temperature phase diagram of dimeric Janus nanoparticles using Molecular Dynamics simulations. The nanoparticle was modeled as a dumbbells particle, and have one monomer that interacts by a standard Lennard Jones potential and another monomer that is modeled using a two-length scale shoulder potential. Monomeric and dimeric systems modeled by this shoulder potential show waterlike anomalies, and we investigate if a Janus nanoparticle composed by one anomalous monomer will exhibit anomalous behavior and self-assembly structures. The influence of the non-anomalous monomer in the dimeric system properties was explored. We show that the diffusion anomaly is maintained, while the density anomaly can disappear depending on the non-anomalous monomer characteristics. As well, the self-assembled structures are affected. Our results are discussed in the basis of the distinct monomer-monomer interactions and on the two-length scale fluid characteristics.

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José Rafael Bordin, Leandro B. Krott, Marcia C. Barbosa. 2015-04-28. Self-Assembly and Waterlike Anomalies in Janus Nanoparticles. https://arxiv.org/abs/1504.07603

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