title: Flexible chains of ferromagnetic nanoparticles.
abstract: We report the fabrication of flexible chains of ferromagnetic Ni nanoparticles that possess the ability to adapt other than the typically observed rigid (nearly) straight configurations in the absence of an external magnetic field. The dynamic mobility of the ferromagnetic chains originates from a layer of densely grafted polyethylene glycol macromolecules enveloping each nanoparticle in the chain. While ferromagnetic chains of unmodified Ni nanoparticles behave as stiff nickel nanorods, the chains made of the grafted nanoparticles demonstrate extreme flexibility. Upon changing the direction of the field, and inevitably going through a zero-field point, the shorter chains undergo chain-globule-chain transformation. The longer chains can bend to a high degree, attaining "snake-like" configurations.
authors.affiliation: Department of Materials Science and Engineering, Clemson University , 161 Sirrine Hall, Clemson, South Carolina 29634, United States.
authors.forename: James
authors.initials: J
authors.lastname: Townsend
authors.forename: Ruslan
authors.initials: R
authors.lastname: Burtovyy
authors.forename: Yuriy
authors.initials: Y
authors.lastname: Galabura
authors.forename: Igor
authors.initials: I
authors.lastname: Luzinov
mesh_terms: D059346:Magnets / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology; D009532:Nickel / Q000737:chemistry
chemical_list: D009532:Nickel