Very slow high-temperature relaxation of the remnant magnetic moment in 2 nm mesomorphic gold nanoparticles

Abstract

The observation at 350 K of an unusually slow relaxation of the remnant magnetization in 2 nm functionalized gold nanoclusters is reported. We show how the magnetic properties seem to be correlated to the supramolecular positional order, which we tentatively ascribe to the symmetry change in the organic shell of the dendronized nanoparticles interacting with a spin glass-type surface magnetism of individual nanoclusters. The dynamics of the relaxation is under the influence of the mesophase via the orientation of the ligands. These observations could help develop new magnetic materials which have magnetic properties that could be controlled by the supramolecular organisation.