The crystal structures of CeSiO4 and Ca2Ce8(SiO4)6O2

J. M.S. Skakle*, C. L. Dickson, F. P. Glasser

*Corresponding author for this work

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Two new solubility-limiting phases relevant to nuclear waste disposal are reported, namely CeSiO4 and Ca2Ce8(SiO4)O2, produced by hydrothermal synthesis at 180°C. X-ray diffraction data are presented for both compounds. Rietveld refinement was performed for each of these phases. CeSiO4 was confirmed to be a zircon structure type, with space group I41/amd, unit cell a=6.9564(3), c=6.1953(4) Å. Bond lengths for SiO4 are in excellent agreement with published values; Ce4+ is coordinated to eight oxygen atoms with four regular and four short bonds. Ca2Ce8(SiO4)O2 was shown to have an apatite structure, with space group P63/m and unit cell a=9.4343(3), c = 6.8885(4) Å. The unit cell and bond lengths were found to be slightly smaller than would be expected from other lanthanide-containing analogs; possible reasons for this are discussed.

Original languageEnglish
Pages (from-to)234-238
Number of pages5
JournalPowder Diffraction
Volume15
Issue number4
DOIs
Publication statusPublished - 31 Dec 2000

    Fingerprint

Keywords

  • Actinide simulants
  • Cement
  • Disposal
  • Nuclear waste
  • Powder diffraction
  • Rietveld refinement

ASJC Scopus subject areas

  • Radiation
  • Materials Science(all)
  • Instrumentation
  • Condensed Matter Physics

Cite this