Clusters: A bridge across the disciplines of physics and chemistry

  1. Puru Jena*,† and
  2. A. W. Castleman, Jr.†,‡
  1. *Department of Physics, Virginia Commonwealth University, Richmond, VA 23284; and
  2. ‡Departments of Chemistry and Physics, Pennsylvania State University, University Park, PA 16802

  1. Edited by Jack Halpern, University of Chicago, Chicago, IL, and approved April 28, 2006 (received for review March 3, 2006)

  1. Fig. 1.
    View larger version:
    Fig. 1.

    Mass spectra and relativity stability of Na clusters. (a) Mass spectrum of sodium clusters, N = 4–75, exhibiting magic numbers. (b) Calculated change in electronic difference, Δ(N + 1) − Δ(N) vs. N. Labels of the peaks correspond to the closed-shell orbitals. This plot was an early illustration of shell effects in metal clusters demonstrating electron shell closure. Insets show results from a range outside of the larger mass spectra (2). [Reprinted with permission from ref. 2 (Copyright 1984, American Physical Society).]


  2. Fig. 2.
    View larger version:
    Fig. 2.

    TOF mass spectrum of multicharged iodine atoms resulting from the Coulomb explosion of HI monomer and HI clusters induced by strong femtosecond laser fields (21). [Reprinted with permission from ref. 21 (Copyright 1994, Elsevier).] Note that the degree of change state varies with the laser fluency.


  3. Fig. 3.
    View larger version:
    Fig. 3.

    Growth patterns of (TiN)n +. (a) TOF mass spectrum of (TiN)n + clusters. Abundance patterns indicate the clusters have cubic structures resembling pieces of the fcc lattice of solid TiN. (b) Proposed structures of (TiN)n + clusters based on magic numbers observed in the mass spectrum (37). [Reprinted with permission from ref. 37 (Copyright 1993, American Institute of Physics).]


  4. Fig. 4.
    View larger version:
    Fig. 4.

    3D data from delayed ionization study of zirconium–carbon system. The peaks that persist in the mass spectra represent those that are undergoing delayed ionizations (44). [Reprinted with permission from ref. 44 (Copyright 2003, American Institute of Physics).]


  5. Fig. 5.
    View larger version:
    Fig. 5.

    Be clusters. (a) Coordination number. (b) Nearest-neighbor distance. (c) HOMO-LUMO gap. (d) Binding energy per atom (54). [Reprinted with permission from ref. 54 (Copyright 2005, American Institute of Physics).]


  6. Fig. 6.
    View larger version:
    Fig. 6.

    Magnetic moments of Fe clusters (69). [Reprinted with permission from ref. 69 (Copyright 1993, American Physical Society).]


  7. Fig. 7.
    View larger version:
    Fig. 7.

    Comparison of condensed phase with cluster data. (a) Plot of Δ(H0,n(Cs+) − ΔH0,n(M+) vs. n showing an asymptotic approach to differences in the total single ion heats of hydration obtained by Randles (R) and Latimer (L) (101). [Image in a reprinted with permission from ref. 101 (Copyright 1970, American Chemical Society).] (b) Ratio of Randles’ total enthalpy of solvation to the partial gas-phase enthalpy of hydration for positive ionic cluster size, n (103). [Image in b reprinted with permission from ref. 103 (Copyright 1986, American Chemical Society).]


  8. Fig. 8.
    View larger version:
    Fig. 8.

    Dynamics of protonated water clusters arising from femtosecond excitation of solvated HBr. The best fit of the data (squares) is shown by the solid line, where t r is the rise time (112). [Reprinted with permission from ref. 112 (Copyright 2002, AAAS, http:www.sciencemag.org).]


  9. Fig. 9.
    View larger version:
    Fig. 9.

    Mass ion intensity and structure of metal–benzene complexes. (a) Mass ion spectra of Sc-Bz (Left), Cr-Bz (Center), and Co-Bz (Right) complexes (127). [Image in a reprinted with permission from ref. 127 (Copyright 1999, American Chemical Society).] (b) Sandwich and rice ball structures of metal–Bz complexes (136). [Image in b reprinted with permission from ref. 136 (Copyright 2001, American Chemical Society).]


  10. Fig. 10.
    View larger version:
    Fig. 10.

    Dependence of magnetic moment of transitional metal atom on support. (a) Magnetic moment of 3d transition-metal atoms supported on metal substrates (144, 145). [Image in a reprinted in part from ref. 144 (Copyright 1996, American Physical Society) and in part from ref. 145 (Copyright 1994, Elsevier).] (b) Magnetic moments of neutral transition-metal atoms, free and supported on benzene (135, 137). [Image in b reprinted with permission from ref. 135 (Copyright 2000, Elsevier).]


  11. Fig. 11.
    View larger version:
    Fig. 11.

    Structure of B12 (a) (152) and Au32 (b) clusters (153). [Image in a reprinted with permission from ref. 152 (Copyright 2003, Nature Publishing Group). Image in b reprinted with permission from ref. 153 (Copyright 2004, Wiley–VCH).]


Footnotes

  • †To whom correspondence may be addressed. E-mail: pjena{at}vcu.edu or awc{at}psu.edu
« Previous | Next Article »Table of Contents

This Article

  1. PNAS July 11, 2006 vol. 103 no. 28 10560-10569
  1. ExtractFree
  2. » Figures Only
  3. Full Text
  4. Full Text (PDF)

Classifications

About Our New Site Design >>
Link: Advanced Search

This Week's Issue

  1. August 19, 2008, 105 (33)
  1. Current Issue
  1. Alert me to new issues of PNAS

Most