Iron polyoxometalate single-molecule magnets

Angew Chem Int Ed Engl. 2009;48(17):3077-81. doi: 10.1002/anie.200900117.

Abstract

Iron sandwich on a tungstate bun: Two new polyoxotungstates with paramagnetic iron(III) heteroatoms (see structure, W blue, Fe yellow, O red) possess S=15/2 and S=5 ground states. Both compounds are single-molecule magnets, and the hexairon species shows large hysteresis (see picture) and quantum tunneling effects at low temperature. Electrochemical studies indicate that these species are stable in solution for a wide range of pH values.