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arXiv · 0906.0030

Magnetic doping of a thiolated-gold superatom

De-en Jiang·Robert L. Whetten
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Abstract

The Au25(SR)18- cluster is a new member in the superatom family which features a centered icosahedral shell (Au13) protected by six RS(AuSR)2 motifs (RS- being a alkylthiolate group). Here we show that this superatom can be magnetically doped by replacing the center Au atom with Cr, Mn, or Fe. We find that Cr and Mn-doped clusters have an optimized magnetic moment of 5 Bohr magnetons while the Fe-doped cluster has an optimized magnetic moment of 3 Bohr magnetons. Although the dopant atom's local magnetic moment makes a major contribution to the total moment, the icosahedral Au12 shell is also found to be significantly magnetized. Our work here provides a new scenario of magnetic doping of a metal-cluster superatom which is protected by ligands and made by wet chemistry.

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De-en Jiang, Robert L. Whetten. 2009-05-29. Magnetic doping of a thiolated-gold superatom. https://doi.org/10.1103/physrevb.80.115402

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