Magnetic Superatoms

ORAL

Abstract

The electronic states in metal clusters are grouped in shells much in the same way as in atoms. Filling of the electronic shells leads to stable species called magic numbers. This has led to the proposition that selected stable metal clusters can mimic chemical properties of atoms in the periodic table and can be classified as superatoms. So far the work on superatoms has focused on non-magnetic species. Here, we propose an extension of the superatom concept to magnetic species by invoking systems that have both localized and delocalized electronic states. Here, the localized electrons stabilize spin magnetic moments while filled nearly free electron shells lead to stable superatoms. We demonstrate it for an isolated VCs$_{8}$ and a ligated MnAu$_{24}$(SH)$_{18}$ motifs that are shown to be magnetic superatoms. The magnetic superatoms assemblies offer prospect of tunable molecular electronic devices, as the coupling can be altered by applying fields.

*We gratefully acknowledge support from U. S. Department of the Army through a MURI Grant \# W911NF-06-1-0280. Part of the computations were performed on the cluster computing facility at HRI, Allahabad.

Authors

  • Jose Reveles

    • Dept of Physics, Virginia Commonwealth University
    • Department of Physics, Virginia Commonwealth University, Richmond, VA 23284, USA
    • Virginia Commonwealth University, Richmond, VA
  • Penee Clayborne

    • Dept of Physics, Virginia Commonwealth University
    • Virginia Commonwealth Univeristy
  • Arthur C. Reber

    • Dept of Physics, Virginia Commonwealth University
  • Shiv Khanna

    • Dept of Physics, Virginia Commonwealth University
    • Dept. of Physics, Virginia Commonwealth University, Richmond, VA 23284
    • Department of Physics, Virginia Commonwealth University, Richmond, VA 23284, USA
    • Virginia Commonwealth University
    • Virginia Commonwealth University, Richmond, VA
  • Kalpataru Pradhan

    • Harish-Chandra Research Institute, India
    • Harish-Chandra Research Institute, Chhatnag Road, Jhusi, Allahabad 211019, India and Virginia Commonwealth University , Richmond, VA 23284, USA
  • Prasenjit Sen

    • Harish-Chandra Research Institute, India
  • Mark Pederson

    • Naval Research Laboratory, Center for Computational Materials Science
    • NRL, Washington DC, U.S.A.