Two-dimensional Monte Carlo simulations to capture thick chainlike clusters of ferromagnetic particles in colloidal dispersions

The present study theoretically investigates the aggregate structures of thick chainlike clusters arising in ferromagnetic colloidal dispersions by means of the cluster-moving Monte Carlo method, Pair correlation functions are also evaluated to clarify the internal structures themselves of such clusters, The following aggregation image of thick chainlike clusters has been obtained from the Monte Carlo simulations for a two-dimensional model system, Particles aggregate to form chainlike clusters when magnetic attractions between particles become strong over a certain value, Such thin chainlike clusters prefer nearly linear formation along a magnetic field direction, if the strength of magnetic field is sufficiently large. In this situation, attractive forces come to act between these nearly linear chainlike clusters, and these forces increase with the lengths of the clusters, Such attractions between the clusters lead to the formation of thick chainlike clusters. (C) 1996 Academic Press, Inc.