Magnetic properties of clusters of supracolloidal magnetic polymers with central attraction

• Published in: Journal of magnetism and magnetic materials Vol. 497; p. 166025
• Main Authors: Novak, E.V., Zverev, V.S., Pyanzina, E.S., Sánchez, P.A., Kantorovich, S.S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.03.2020; Elsevier BV
• Subjects: Attraction; Clusters; Crosslinking; Initial susceptibility; Langevin dynamics simulations; Magnetic moments; Magnetic permeability; Magnetic properties; Magnetism; Polymers; Rings (mathematics); Stockmayer interaction; Supracolloidal magnetic polymers; Topology; Stockmayer interaction; Supracolloidal magnetic polymers; Initial susceptibility; Langevin dynamics simulations; Magnetic properties
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2019.166025

•Computer simulations of the clusters made of supracolloidal magnetic polymers (SMPs).•Central attraction leads to decrease of the suspension initial susceptibility of SMPs.•Chain-like SMPs form vortex structures with negligible magnetic moments. Supracolloidal magnetic polymers (SMPs) are structures made by crosslinking magnetic particles. In this work, using Langevin dynamics simulations, we study the zero-field magnetic properties of clusters formed in suspensions of SMPs with different topologies – chains, rings, X and Y – that interact via Stockmayer potential. We find that the presence of central attraction, resulting in the formation of large compact clusters, leads to a dramatic decrease of the suspension initial susceptibility, independently from SMP topology. However, the largest decrease corresponds to chain-like SMPs with strongly interacting particles. This is due to the higher rotational degrees of freedom of SMPs with such topology, which allows the particles to reorganise themselves inside the clusters in such a way that their magnetic moments form energetically advantageous vortex structures with negligible net magnetic moments.