Magnetic proximity effect in ferrimagnetic–ferromagnetic core–shell Prussian blue analogues molecular magnet

Highlights: • Synthesis of ferrimagnetic–ferromagnetic core–shell Prussian blue analogues molecular magnet, Mn_1.5[Cr(CN)₆]·mH₂[email protected]_1.5[Cr(CN)₆]·nH₂O. • Magnetic proximity effect in core–shell structure of Mn_1.5[Cr(CN)₆]·mH₂[email protected]_1.5[Cr(CN)₆]·nH₂O. • Enhancement of Curie temperature (T_C ∼70 K) for the core–shell compound. • Observation of neutron depolarization below ∼70 K for core–shell structure. A magnetic proximity effect has been observed in core–shell structure of molecular magnet, Mn_1.5[Cr(CN)₆]·mH₂[email protected]_1.5[Cr(CN)₆]·nH₂O, synthesized using a ferrimagnetic core of Mn_1.5[Cr(CN)₆]·7.5H₂O surrounded by a ferromagnetic shell of Ni_1.5[Cr(CN)₆]·7.5H₂O. The values of Curie temperature (T_C) are found to be of ∼65 and ∼60 K for the bare–core and bare–shell compounds, respectively. However, an enhanced T_C (∼70 K) has been observed for the core–shell structure. The proximity effect (due to presence of interface exchange coupling) between core and shell is responsible for the observed enhancement of T_C. A neutron depolarization study also confirms finite depolarization below ∼70 K.