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The First Cobalt Single-Molecule Magnet

En-Che Yang·David N Hendrickson·Wolfgang Wernsdorfer·Motohiro Nakano·Roger Sommer·Arnold L Rheingold·Marisol Ledezma-Gairaud·George Christou
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Abstract

The first cobalt molecule to function as a single-molecule magnet, [Co4(hmp)4(MeOH)4Cl4], where hmp- is the anion of hydroxymethylpyridine, is reported. The core of the molecule consists of four Co(II) cations and four hmp- oxygen atoms ions at the corners of a cube. Variable-field and variable-temperature magnetization data have been analyzed to establish that the molecule has a S=6 ground state with considerable negative magnetoanisotropy. Single-ion zero-field interactions (DSz2) at each cobalt ion are the origin of the negative magnetoanisotropy. A single-crystal of the compound was studied by means of a micro-SQUID magnetometer in the range of 0.040-1.0K. Hysteresis was found in the magnetization versus magnetic field response of this single crystal. It is concluded that this is the first cobalt molecule to function as a single-molecule magnet.

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En-Che Yang, David N Hendrickson, Wolfgang Wernsdorfer, Motohiro Nakano, Roger Sommer, Arnold L Rheingold, Marisol Ledezma-Gairaud, George Christou. 2001-09-12. The First Cobalt Single-Molecule Magnet. https://doi.org/10.1063/1.1450813

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