Researchers discover superatoms with magnetic shells
A team of Virginia Commonwealth University scientists has discovered a new class of “superatoms” — a stable cluster of atoms that can mimic different elements of the periodic table — with unusual magnetic characteristics that may have applications in spintronics.
The team examined the electronic and magnetic properties of clusters having one iron atom surrounded by multiple magnesium atoms.
The team found that when the cluster had eight magnesium atoms, it acquired extra stability due to filled electronic shells that were far separated from the unfilled shells.
The new cluster had a magnetic moment of four Bohr magnetons, which is almost twice that of an iron atom in solid iron magnets. There are only nine known elements that exhibit magnetic character in solid form.
This could lead to significant developments in the area of molecular electronics where such devices allow the flow of electrons with particular spin orientation desired for applications such as quantum computers, the scientists said.
Ref.: Victor M. Medel, et al., Hund’s rule in superatoms with transition metal impurities, PNAS, 2011; [DOI: 10.1073/pnas.1100129108]