Structural stability in high temperature Pu and Pu alloys

Wills, John; Roder, Heinrich; Eriksson, Olof R.
July 2000
AIP Conference Proceedings;2000, Vol. 532 Issue 1, p426
Academic Journal
It is generally accepted that the properties of the high-temperature phases require a reduction in bonding coming from 5f electrons, but the source of this reduction has not been determined. Strong electron correlations and localization driven by structural distortion are two of the suggestions that have been put forward. Attempts to include electron correlation beyond the local density approximation have been limited to phenomenological Hamiltonians lacking sufficient accuracy to deal with, and be tested against, real materials and structures. At the present time, the size of a unit cell necessary for a realistic study of disorder effects is prohibitively large. We have developed a model, which we call the mixed-level state, that relies only on the assumption that partial localization of the 5f manifold is responsible for the reduced bonding. The mixed-level model is quite successful in describing the basic structural properties of delta Pu and Pu-Ga stochiometric alloys. © 2000 American Institute of Physics.


Related Articles

  • Outstanding Meeting Paper/Review: Introduction to first-principles electronic structure methods: Application to actinide materials. Klepeis, John E. // Journal of Materials Research;Dec2006, Vol. 21 Issue 12, p3 

    This paper provides an introduction for non-experts to first-principles electronic structure methods that are widely used in condensed-matter physics. Particular emphasis is placed on giving the appropriate background information needed to better appreciate the use of these methods to study...

  • How accurate are electronic structure methods for actinoid chemistry? Averkiev, Boris; Mantina, Manjeera; Valero, Rosendo; Infante, Ivan; Kovacs, Attila; Truhlar, Donald; Gagliardi, Laura // Theoretical Chemistry Accounts: Theory, Computation, & Modeling;Jul2011, Vol. 129 Issue 3-5, p657 

    The CASPT2, CCSD, and CCSD(T) levels of wave function theory and seven density functionals were tested against experiment for predicting the ionization potentials and bond dissociation energies of actinoid monoxides and dioxides with their cations. The goal is to guide future work by enabling...

  • Actinide electronic structure and atomic forces. Albers, R. C.; Rudin, Sven P.; Trinkle, Dallas R.; Jones, M. D. // AIP Conference Proceedings;2000, Vol. 532 Issue 1, p412 

    We have developed a new method[1] of fitting tight-binding parameterizations based on functional forms developed at the Naval Research Laboratory.[2] We have applied these methods to actinide metals and report our success using them (see below). The fitting procedure uses first-principles...

  • Electronic structure of U4+, Np4+, and Pu4+ doped into ThSiO4 single crystal. Krupa, J. C.; Carnall, W. T. // Journal of Chemical Physics;12/1/1993, Vol. 99 Issue 11, p8577 

    The optical spectra of tetravalent ions of early actinides, U4+, Np4+, and Pu4+, were interpreted via a semiempirical Hamiltonian in D2d site symmetry, in terms of electronic transitions within their respective 5fn ground state configurations. Systematic trends in the semiempirical parameters...

  • Modeling of Zircon (ZrSiO4) and Zirconia (ZrO2) using ADF-GUI Software. Lwin, Maung Tin Moe; Amin, Yusoff Mohd; Kassim, Hasan Abu; Kamaluddin, Burhanuddin // AIP Conference Proceedings;7/7/2010, Vol. 1250 Issue 1, p265 

    Natural zircon (ZrSiO4) has very high concentration of Uranium and Thorium of up to 5000 ppm [1]. Radioactive decay process of alpha particles from these impurities affects some changes like several atomic displacements in the crystalline structure of zircon. The amount of track density caused...

  • Ab initio all-electron Dirac–Fock–Breit calculations for UF6. Malli, Gulzari L.; Styszynski, Jacek // Journal of Chemical Physics;1/15/1996, Vol. 104 Issue 3, p1012 

    Ab initio all-electron Dirac–Fock, Dirac–Fock–Breit, and Hartree–Fock calculations are reported for UF6, assuming the experimental octahedral geometry. The spin–orbit (S–O) splitting is calculated for all the ground state levels of UF6 and the calculated...

  • Theoretical studies of actinyl crown ether inclusion complexes. Martin, Richard L.; Jeffrey Hay, P.; Schreckenbach, Georg // AIP Conference Proceedings;2000, Vol. 532 Issue 1, p392 

    Clark et al. recently reported the synthesis of the NpO[sub 2][sup +]ion encapsulated by the 18-crown-6 ligand. The [NpO[sub 2](18-crown-6)]ClO[sub 4] salt was characterized crystallographically and shown to have six approximately coplanar crown ether oxygen atoms coordinated to a central...

  • Semiclassical Description of Shell Effects in Atomic Clusters. Shpatakovskaya, G. V. // Journal of Experimental & Theoretical Physics;Jul2000, Vol. 91 Issue 1, p76 

    The density functional method for a system of electrons in an external field is applied to derive an expression for the correction to the free energy for a small change in electron density. This expression is used for a semiclassical description of shell effects in atomic clusters at both zero...

  • A new chemical concept: Shape chemical potentials. Chan, Garnet Kin-Lic; Handy, Nicholas C. // Journal of Chemical Physics;10/15/1998, Vol. 109 Issue 15, p6287 

    Examines shape chemical potential within the density functional formalism. Importance for describing electron withdrawing ability of density fragments; Connection of shape connection potential with Sanderson's principle; Discussion of shape chemical concept for chemical features.


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics