IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Surface Science Thursday Sessions
       Session SS2-ThM

Paper SS2-ThM4
Resonant Photoemission Investigation of the Electronic Structure of Plutonium

Thursday, November 1, 2001, 9:20 am, Room 122

Session: Electronic Structure II
Presenter: J.G. Tobin, Lawrence Livermore National Laboratory
Authors: J.G. Tobin, Lawrence Livermore National Laboratory
D.A. Arena, Lawrence Livermore National Laboratory
J. Terry, Los Alamos National Laboratory
R.K. Schulze, Los Alamos National Laboratory
J.D. Farr, Los Alamos National Laboratory
T. Zocco, Los Alamos National Laboratory
K. Heinzelman, Lawrence Berkeley National Laboratory
E. Rotenberg, Lawrence Berkeley National Laboratory
D. Shuh, Lawrence Berkeley National Laboratory
G. van der Laan, Daresbury Lab, UK
Correspondent: Click to Email
The valence electronic structures of the actinide metals and alloys in general and plutonium (Pu) in particular remain mired in controversy. Interestingly, the various phases of Pu metal provide a mirocosm of the metallic actinides as a whole. Thus, unravelling the nuances of the interplay of electronic and geometric structures in Pu will illuminate the properties of all transuranic metals. In a sense, the behavior of the Pu 5f electrons is completely counter-intuitive. The dense phase, a, has some semblance of delocalization in the 5f valence bands and can be treated theoretically within single electron models such as the Local Density Approximation (LDA). The a phase is monoclinic, which is a low symmetry ordering. The less dense d-phase is fcc and exhibits evidence of localized and/or correlated electronic behavior. Experimental Resonant Photoemission (ResPes) results for a- Pu and d- Pu bulk samples will be presented and compared to the results of an atomic model calculation. Both Pu samples exhibit limited agreement with the atomic model calculations. As expected, a- Pu appears to have more 5f valence band delocalization than d-Pu. Evidence of an enhanced sensitivity to surface corruption, by using synchrotron radiation as the excitation, will be presented. This work was performed under the auspices of the U.S Department of Energy by Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48. Los Alamos National Laboratory is operated by the University of California under Contract No. W-7405- ENG-36. Experiments were carried out at the Spectromicroscopy Facility (Beamline 7.0) at the Advanced Light Source, built and supported by the U.S. Department of Energy. The Advanced Light Source and DKS are supported by the Director, Office of Science, Office of Basic Energy Sciences, Matl. and Chem. Sciences Divisions, of the U.S. DOE under Contract No. DE-AC03-76SF00098 at Lawrence Berkeley National Laboratory.