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Studies of Vibrational Properties in Ga Stabilized d-Pu by Extended X-ray Absorption Fine Structure

P. G. Allen·A. L. Henderson·E. R. Sylwester·P. E. A. Turchi·T. H. Shen·G. F. Gallegos·C. H. Booth
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Abstract

Temperature dependent extended x-ray absorption fine structure (EXAFS) spectra were measured for a 3.3 at% Ga stabilized Pu alloy over the range T= 20 - 300 K at both the Ga K-edge and the Pu L_III-edge. The temperature dependence of the pair-distance distribution widths, σ(T) was accurately modeled using a correlated-Debye model for the lattice vibrational properties, suggesting Debye-like behavior in this material. We obtain pair- specific correlated-Debye temperatures, Θ_cD, of 110.7 +/- 1.7 K and 202.6 +/- 3.7 K, for the Pu-Pu and Ga-Pu pairs, respectively. These results represent the first unambiguous determination of Ga-specific vibrational properties in PuGa alloys, and indicate the Ga-Pu bonds are significantly stronger than the Pu-Pu bonds. This effect has important implications for lattice stabilization mechanisms in these alloys.

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P. G. Allen, A. L. Henderson, E. R. Sylwester, P. E. A. Turchi, T. H. Shen, G. F. Gallegos, C. H. Booth. 2002-05-03. Studies of Vibrational Properties in Ga Stabilized d-Pu by Extended X-ray Absorption Fine Structure. https://doi.org/10.1103/physrevb.65.214107

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