Fe3O4 Nanocrystals Tune the Magnetic Regime of the Fe/Ni Molecular Magnet: A New Class of Magnetic Superstructures
journal contributionposted on 15.07.2013, 00:00 by Giorgio Zoppellaro, Jiří Tuček, Radovan Herchel, Klára Šafářová, Radek Zbořil
A new class of organometallic–inorganic magnetic material was engineered by a sonochemically assisted self-assembly process between magnetite nanoparticles (biogenic Fe3O4, hard constituent) functionalized with isonicotinic acid and a metamagnetic organometallic complex ([Ni(en)2]3[Fe(CN)6]2·3H2O, soft constituent). In such bottom-up methodology, hard and soft counterparts form well-organized microdimensional clusters that showed morphological fingerprints and magnetic behavior clearly distinct from those of the initial building units. In the engineered soft–hard material, the magnetite nanocrystals induced ferromagnetic ordering at room temperature of closer contact layers of [Ni(en)2]3[Fe(CN)6]2·3H2O, thus demonstrating the ability to sensibly modify the [Ni(en)2]3[Fe(CN)6]2·3H2O paramagnetic regime. The magnetic ordering of [Ni(en)2]3[Fe(CN)6]2·3H2O was triggered by the intrinsic local field of the hard magnetic nanocrystals, which resembled, to some extent, the effects promoted by large, external magnetic fields.