Branching points in the low-temperature dipolar hard sphere fluid

Author(s)
Lorenzo Rovigatti, Sofia Kantorovich, Alexey O. Ivanov, Jose Maria Tavares, Francesco Sciortino
Abstract

In this contribution, we investigate the low-temperature, low-density behaviour of dipolar hard-sphere (DHS) particles, i.e., hard spheres with dipoles embedded in their centre. We aim at describing the DHS fluid in terms of a network of chains and rings (the fundamental clusters) held together by branching points (defects) of different nature. We first introduce a systematic way of classifying inter-cluster connections according to their topology, and then employ this classification to analyse the geometric and thermodynamic properties of each class of defects, as extracted from state-of-the-art equilibrium Monte Carlo simulations. By computing the average density and energetic cost of each defect class, we find that the relevant contribution to inter-cluster interactions is indeed provided by (rare) three-way junctions and by four-way junctions arising from parallel or anti-parallel locally linear aggregates. All other (numerous) defects are either intra-cluster or associated to low cluster-cluster interaction energies, suggesting that these defects do not play a significant part in the thermodynamic description of the self-assembly processes of dipolar hard spheres.

Organisation(s)
Computational and Soft Matter Physics
External organisation(s)
Sapienza University of Rome, Instituto Politécnico de Lisboa, Universidade Técnica de Lisboa, Ural Federal University
Journal
Journal of Chemical Physics
Volume
139
No. of pages
9
ISSN
0021-9606
DOI
https://doi.org/10.1063/1.4821935
Publication date
10-2013
Peer reviewed
Yes
Austrian Fields of Science 2012
103023 Polymer physics, 103017 Magnetism, 103029 Statistical physics
Keywords
Portal url
https://ucrisportal.univie.ac.at/en/publications/6a57cf44-10f0-40d1-a96c-51c42cdd478e