doi:10.1038/nindia.2009.158 Published online 22 June 2009
An Indo-US research team has discovered a new cluster consisting of one vanadium and eight cesium atoms1.
This new cluster of atoms acts like a tiny magnet and mimics a single manganese atom in magnetic strength. Christened magnetic superatoms, this new cluster will have a wide range of applications in making molecular devices for non-volatile data storage and high data processing.
Superatoms could be plodded to design building blocks for nanomaterials with desired properties. Having no unpaired electron, superatoms are non-magnetic. To devise magnetic superatoms, the researchers carried out studies to make composite superatoms. For this the researchers took atoms of vanadium, sodium and cesium.
When they tested a cluster of eight cesium atoms with one vanadium atom, it exhibited extra stability due to a filled electronic state. An atom is in a stable configuration when its outermost shell is full. The new cluster had a magnetic moment of five, which is more than twice the value for an iron atom in a solid iron magnet. A magnetic moment is a measure of the internal magnetism of the cluster.
Cesium is a good conductor of electricity and hence the superatom combines the benefit of magnetic character along with ease of conduction through its outer skin. The new cluster will have applications in spintronics, a process using electron spin to synthesize new devices for memory and data processing, the researchers say.
The authors of this work are from: Department of Physics, Virginia Commonwealth University; Naval Research Laboratory, Center for Computational Materials Science, Washington DC, USA and Harish-Chandra Research Institute, Allahabad, India.
- Reveles, U. J. et al. Designer magnetic superatoms. Nat. Chem. doi: 10.1038/nchem.249 (2009)