Metal hexacyanochromate coordination nanopolymers: Surface ligand effect on their magnetism

We synthesized nanometric metal hexacyanochromate coordination polymers (CrM–L, M = Ni, Fe) stabilized by different alkyl ligands L (L = stearylamine (SA), 4-(dioctadecylamino)pyridine (OPy)) and revealed that the ferromagnetism of CrM–L was dominated by the type of L. OPy acted as positive to increase the ferromagnetic critical temperature and the saturation magnetization of CrNi–L. Furthermore, the magnetization of CrFe–L disappeared when SA was introduced. This ligand effect on the magnetism of CrM–L originated from the difference in the number of L attached to CrM–L nanoparticles.