Kantorovich, Sofia S.Ivanov, Alexey O.Rovigatti, LorenzoTavares, JoseSCIORTINO, Francesco2016-03-182016-03-182015KANTOROVICH, Sofia S. [et al.] - Temperature-induced structural transitions in self-assembling magnetic nanocolloids. PCCP - Physical Chemistry Chemical Physics. ISSN. 1463-9076. Vol. 17, N.º 25 (2015), pp. 16601-166081463-90761463-9084http://hdl.handle.net/10400.21/5921With the help of a unique combination of density functional theory and computer simulations, we discover two possible scenarios, depending on concentration, for the hierarchical self-assembly of magnetic nanoparticles on cooling. We show that typically considered low temperature clusters, i.e. defect-free chains and rings, merge into more complex branched structures through only three types of defects: four-way X junctions, three-way Y junctions and two-way Z junctions. Our accurate calculations reveal the predominance of weakly magnetically responsive rings cross-linked by X defects at the lowest temperatures. We thus provide a strategy to fine-tune magnetic and thermodynamic responses of magnetic nanocolloids to be used in medical and microfluidics applications.engDipolar hard-spheresMonte-CarloNanoparticlesColloidsFerrofluidsParticlesFluidPolymersPhaseFieldjournal article10.1039/c5cp01558h