Magnetic Superatoms

Small metal clusters called superatoms that mimic the properties of individual atoms are of interest as potential building blocks for nanostructured materials. Magnetic superatoms in particular could be used in so-called spintronic devices, which store information using electron spins rather than charges. Although a variety of superatoms have been made, a team led by Shiv N. Khanna of Virginia Commonwealth University and Kit H. Bowen Jr. of Johns Hopkins University reports the first synthesis of magnetic superatoms (J. Am. Chem. Soc., DOI: 10.1021/ja400830z). The researchers prepared vanadium-sodium clusters using a pulsed arc cluster ionization source to vaporize metal electrodes. They studied the resulting clusters by photoelectron spectroscopy and computational methods. The results show that VNa₈ and VNa₇^– are magnetic superatoms with valence electron configurations resembling those of manganese atoms, whereas VNa₈^– and VNa₉ resemble chromium. Further research is needed to improve the synthesis and to stabilize the clusters, the researchers say, but the strong spin magnetic moments of the clusters suggest they could be used in spintronics.