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DOE OSTI · 1289231

Materials Data on Ce3Th2O9 by Materials Project

Abstract

Th2Ce3O9 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Th4+ sites. In the first Th4+ site, Th4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Th–O bond distances ranging from 2.38–2.57 Å. In the second Th4+ site, Th4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Th–O bond distances ranging from 2.39–2.54 Å. There are three inequivalent Ce+3.33+ sites. In the first Ce+3.33+ site, Ce+3.33+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ce–O bond distances ranging from 2.27–2.42 Å. In the second Ce+3.33+ site, Ce+3.33+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ce–O bond distances ranging from 2.33–2.53 Å. In the third Ce+3.33+ site, Ce+3.33+ is bonded to seven O2- atoms to form distorted edge-sharing CeO7 hexagonal pyramids. There are a spread of Ce–O bond distances ranging from 2.34–2.50 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form distorted OCe3Th tetrahedra that share corners with sixteen OCe3Th tetrahedra and edges with four OCeTh3 tetrahedra. In the second O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form OCe3Th tetrahedra that share corners with thirteen OCe3Th tetrahedra and edges with six OCe4 tetrahedra. In the third O2- site, O2- is bonded to two equivalent Th4+ and two Ce+3.33+ atoms to form OCe2Th2 tetrahedra that share corners with sixteen OCe3Th tetrahedra and edges with five OCe2Th2 tetrahedra. In the fourth O2- site, O2- is bonded to four Ce+3.33+ atoms to form OCe4 tetrahedra that share corners with fifteen OCe3Th tetrahedra and edges with four OCe2Th2 tetrahedra. In the fifth O2- site, O2- is bonded to two Th4+ and two equivalent Ce+3.33+ atoms to form OCe2Th2 tetrahedra that share corners with fourteen OCe3Th tetrahedra and edges with six OCe4 tetrahedra. In the sixth O2- site, O2- is bonded to three Th4+ and one Ce+3.33+ atom to form a mixture of edge and corner-sharing OCeTh3 tetrahedra. In the seventh O2- site, O2- is bonded to three Th4+ and one Ce+3.33+ atom to form OCeTh3 tetrahedra that share corners with fifteen OCe3Th tetrahedra and edges with six OCe2Th2 tetrahedra. In the eighth O2- site, O2- is bonded to two equivalent Th4+ and two Ce+3.33+ atoms to form OCe2Th2 tetrahedra that share corners with thirteen OCe3Th tetrahedra and edges with six OCe4 tetrahedra. In the ninth O2- site, O2- is bonded to two Th4+ and two equivalent Ce+3.33+ atoms to form distorted OCe2Th2 tetrahedra that share corners with fourteen OCe3Th tetrahedra and edges with five OCe2Th2 tetrahedra.

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2020-07-20. Materials Data on Ce3Th2O9 by Materials Project. https://doi.org/10.17188/1289231

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