Authors: T. Mori
Affilation: National Institute for Materials Science, Japan
Pages: 5 - 8
Keywords: cluster, borides, antiferromagnetic, f electron, icosahedron, ESR, magnetic interaction
Rare earth borides containing the B12 icosahedron display surprisingly strong magnetic interactions although they are magnetically dilute insulating materials with localized f-electrons. A microscopic local probe, ESR, was utilized to investigate the mechanism of the interaction. From detailed analysis of the spectra of a ladder-like Gd borosilicide, it was indicated that the Gd atoms are coupled along the 1D infinite chain of the atomic ladder rather than between the rungs which is actually the shorter metal-metal spacing. The 1D atomic chain is along an infinite chain of B12 icosahedra and this result is consistent with the idea that the boron icosahedra clusters are functioning as a new mediator of magnetic interaction. This is striking because it is the discovery of a new magnetic mediator, which simultaneously serves as a nanostructural building block for formation of these cluster compounds.