High inertness of W@Si 12 cluster toward O 2 molecule

Abstract

The geometry, electronic structure, and reactivity with O 2 molecules of an isolated W@Si 12 cluster have been investigated by first principles simulations. The results confirm that O 2 can weakly adsorb on the HP-W@Si 12 cage with a binding energy of 0.004 to 0.027 eV. O 2 may dissociate on the cluster by overcoming energy barrier of at least 0.593 eV. However, this is a spin-forbidden reaction, rendering the high inertness of the HP-W@Si 12 cluster toward O 2. These results confirm the high inertness of the W@Si 12 cluster toward O 2 molecules in ambient conditions, in close agreement with experimental observations of magic cluster of W@Si 12. © 2012 Elsevier B.V. All rights reserved.