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Updated: Dec 14, 2025
Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV
Published on: December 29, 2016
Targeting complex plutonium oxides by combining crystal chemical reasoning with density-functional theory
Kristen A Pace1, Vladislav V Klepov2, Matthew S Christian3
1Center for Hierarchical Waste form Materials, Columbia, South Carolina 29208, USA. zurloye@mailbox.sc.edu and Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA.
Abstract:
The stability of the novel Pu(iv) silicate, Cs2PuSi6O15, was predicted from a combination of crystal chemical reasoning and DFT calculations and confirmed by its synthesis via flux crystal growth. Formation enthalpies of the A2MSi6O15 (A = Na-Cs; M = Ce, Th, U-Pu) compositional family were calculated and indicated the Cs-containing phases should preferentially form in the Cmc21 structure type, consistent with previous experimental findings and the novel phases produced in this work, Cs2PuSi6O15 and Cs2CeSi6O15. The formation enthalpies of a second set of compositions, A2MSi3O9, were also calculated and a comparison between the two compositional families correctly predicted A2MSi6O15 to be on average more stable than A2MSi3O9.
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