Ferromagnetic order and spin-glass behavior in multi-metallic compound Ni[sub]1.125Co[sub]0.375[Fe(CN)[sub]6] [sup]. 6.8H[sub]2O

Multi-metallic Prussian blue compound Ni[sub]1.125Co[sub]0.375[Fe(CN)[sub]6] [sup]. 6.8H[sub]2O has been synthesized. The Moessbauer spectroscopy at room temperature and IR spectra study revealed that the metal ions are bonded through cyanide ligand and the presence of low spin Fe[super]III(S = 1/2) and high spin Fe[super]III(S = 5/2) ions, as showed in these structure: Fe[super]III(S = 1/2)-CN- (Co[super]II/Ni[super]II)(96%) and Fe[super]III(S = 5/2)-NC-(Co[super]II/Ni[super]II) (4%). The Curie constant of C = 3.00 cm[super]3 K mol[super]-1 and Weiss paramagnetic Curie temperature of [theta] = 16.43 K were observed in fitting according to Curie-Weiss law. These results indicate that there existed a ferromagnetic exchange interaction in the complexes. The observed value of coercive field (H[sub]c) and remanent magnetization (M[sub]r) at 4 K for the compound are 497 Oe and 1.03 N[beta]. The presence of spin- glass behaviours in the compound is ascribed mainly to domain mobility or domain growth under different cooling conditions.