Magnetic behaviour of negatively charged nickel(II) hexacyanoferrate(III) coordination nanoparticles

Negatively charged 4 nm bimetallic Ni II –Fe III cyanide-bridged nanoparticles were obtained and isolated by different coating agents. The magnetic properties of the particles were studied in the powder form and in diluted samples. A spin-glass like behaviour occurs in the concentrated sample, while the magnetic behaviour of the diluted ones strongly depends on the method used to isolate the nanoparticles. Only high dilution in a polymer matrix leads to a single-domain superparamagnetic behaviour, with a blocking temperature of 3.5 K.