A Proton Conducting Single-ion Magnet Based on a Mononuclear Dy(III) Complex

Crystalline molecular materials exhibiting both proton conduction and single-molecule magnet (SMM) behaviors would offer a great opportunity for applications in fuel cells, molecular spintronics and high-density data storage technologies. However, such kind of materials have rarely been reported. Herein, the first example of mononuclear proton-conductive DyIII-SMM, namely [Dy(H2bim)2(H2O)2(NO3)2](NO3) (1) (H2bim = 2,2’-biimidazole), was synthesized and characterized. Complex 1 displays a high proton conductivity (σ) of 1.26×10–3 S cm–1 at room temperature under 100% relative humidity (RH). 1D H-bonding network constructed from 2,2’-biimidazole and coordinated water molecules as H-bonding donors and nitrate anions (NO3–) as H-bonding acceptors play dominant role in this high conductivity. Magnetic studies indicated that complex 1 exhibit signle-ion magnet.