The First Cobalt Single-Molecule Magnet

Authors :: Yang, En-Che
Hendrickson, David N
Wernsdorfer, Wolfgang
Nakano, Motohiro
Sommer, Roger
Rheingold, Arnold L
Ledezma-Gairaud, Marisol
Christou, George
Publication Year :: 2001
Publisher :: arXiv, 2001.
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.<br />Comment: 10 pages, 4 figure, 2001 MMM conference