Controlled self-assembly of colloidal cobalt nanocrystals mediated by magnetic interactions
نویسندگان
چکیده
We demonstrate the possibility of obtaining a rich set of self-assembled arrays from a single component cobalt nanocrystal (NC) system by a controlled variation of size, shape and inter-particle interactions. By selecting appropriate conditions in which one of a set of weak but competing interaction forces (steric, van der Waals, depletion, or magnetostatic) dominates we can reproducibly achieve a wide range of nanocrystal arrays. This includes hexagonal and square arrays, arrays spatially segregated by size, linear chains and lyotropic crystals exhibiting increased orientation order as a function of concentration. r 2003 Published by Elsevier B.V. PACS: 75.50.k; 64.60.l; 75.10; 61.30.g
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