title: Branching points in the low-temperature dipolar hard sphere fluid.
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.
authors.affiliation: Dipartimento di Fisica, Sapienza Università di Roma, Piazzale A. Moro 2, 00185 Roma, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Rovigatti
authors.forename: Sofia
authors.initials: S
authors.lastname: Kantorovich
authors.forename: Alexey O
authors.initials: AO
authors.lastname: Ivanov
authors.forename: José Maria
authors.initials: JM
authors.lastname: Tavares
authors.forename: Francesco
authors.initials: F
authors.lastname: Sciortino
mesh_terms: D003080:Cold Temperature; D009010:Monte Carlo Method; D052638:Particulate Matter
chemical_list: D052638:Particulate Matter