Directional self-assembly of permanently magnetised nanocubes in quasi two dimensional layers

Author(s)
Joe G. Donaldson, Sofia S. Kantorovich
Abstract

To design modern materials with a specific response, the consequences of directionally dependent interactions on the self-assembly of constituent nanoparticles need to be properly understood. Directionality arises in the study of anisometric nanoparticles, where geometry has a drastic effect on the properties observed. Given the fact that magnetic interactions are inherently anisotropic, if one constructs these particles from a magnetic medium, an interesting interplay between the two sources of directionality will occur. We have investigated this scenario by exploring systems of dipolar nanocube monolayers. Using an applied analytical approach, in combination with molecular dynamics simulations, we have determined the ground state structures of individual monolayer clusters. Taking inspiration from experiments, two different fixed dipole orientations for the permanent magnetisation of the nanocubes were considered: the first aligned along the [001] crystallographic axis of each cube, and the second along the [111] axis. We discovered that the structure of the ground state is distinctly different for the two systems of permanently magnetised nanocubes; [001] cubes form dipolar chains in the ground state, whereas those with [111] orientation adopt square lattice structures. The discovered configurations in the ground state represent two different structural motifs, as yet unobserved in the ground state of other magnetic nanoparticle systems.

Organisation(s)
Computational and Soft Matter Physics
External organisation(s)
Ural Federal University
Journal
Nanoscale
Volume
7
Pages
3217-3228
No. of pages
12
ISSN
2040-3364
DOI
https://doi.org/10.1039/c4nr07101h
Publication date
2015
Peer reviewed
Yes
Austrian Fields of Science 2012
103023 Polymer physics, 103017 Magnetism, 103018 Materials physics, 210006 Nanotechnology
Keywords
ASJC Scopus subject areas
General Materials Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/eb6fe695-b749-41db-a5df-2f7442c804d8