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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on CeThO4 by Materials Project

ThCeO4 is Fluorite-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Th4+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Th–O bond lengths are 2.41 Å. Ce4+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Ce–O bond lengths are 2.39 Å. O2- is bonded to two equivalent Th4+ and two equivalent Ce4+ atoms to form a mixture of corner and edge-sharing OCe2Th2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce6Th4O19 by Materials Project

Th4Ce6O19 crystallizes in the monoclinic Cm 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 2.37–2.47 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 2.38–2.51 Å. There are four inequivalent Ce+3.67+ sites. In the first Ce+3.67+ site, Ce+3.67+ is bonded to seven O2- atoms to form a mixture of distorted edge and corner-sharing CeO7 hexagonal pyramids. There are a spread of Ce–O bond distances ranging from 2.35–2.37 Å. In the second Ce+3.67+ site, Ce+3.67+ is bonded to seven O2- atoms to form a mixture of distorted edge and corner-sharing CeO7 hexagonal pyramids. There are a spread of Ce–O bond distances ranging from 2.35–2.37 Å. In the third Ce+3.67+ site, Ce+3.67+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Ce–O bond distances ranging from 2.36–2.59 Å. In the fourth Ce+3.67+ site, Ce+3.67+ is bonded to seven O2- atoms to form a mixture of distorted edge and corner-sharing CeO7 hexagonal pyramids. There are a spread of Ce–O bond distances ranging from 2.31–2.36 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded to three Th4+ and one Ce+3.67+ atom to form a mixture of edge and corner-sharing OCeTh3 tetrahedra. In the second O2- site, O2- is bonded to four Ce+3.67+ atoms to form OCe4 tetrahedra that share corners with fourteen OCe4 tetrahedra and edges with six OCe3Th tetrahedra. In the third O2- site, O2- is bonded to four Ce+3.67+ atoms to form a mixture of edge and corner-sharing OCe4 tetrahedra. In the fourth O2- site, O2- is bonded to four Ce+3.67+ atoms to form OCe4 tetrahedra that share corners with fourteen OCeTh3 tetrahedra and edges with five OCe4 tetrahedra. In the fifth O2- site, O2- is bonded to one Th4+ and three Ce+3.67+ atoms to form a mixture of edge and corner-sharing OCe3Th tetrahedra. In the sixth O2- site, O2- is bonded to three Th4+ and one Ce+3.67+ atom to form OCeTh3 tetrahedra that share corners with fifteen OCeTh3 tetrahedra and edges with six OCe3Th tetrahedra. In the seventh O2- site, O2- is bonded to one Th4+ and three Ce+3.67+ atoms to form OCe3Th tetrahedra that share corners with fourteen OCe4 tetrahedra and edges with six OCeTh3 tetrahedra. In the eighth O2- site, O2- is bonded to one Th4+ and three Ce+3.67+ atoms to form distorted OCe3Th tetrahedra that share corners with sixteen OCeTh3 tetrahedra and edges with five OCe4 tetrahedra. In the ninth O2- site, O2- is bonded to three Th4+ and one Ce+3.67+ atom to form OCeTh3 tetrahedra that share corners with sixteen OCe4 tetrahedra and edges with six OCe3Th tetrahedra. In the tenth O2- site, O2- is bonded to three Th4+ and one Ce+3.67+ atom to form a mixture of edge and corner-sharing OCeTh3 tetrahedra. In the eleventh O2- site, O2- is bonded to one Th4+ and three Ce+3.67+ atoms to form distorted OCe3Th tetrahedra that share corners with sixteen OCeTh3 tetrahedra and edges with five OCe4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CeTh2O6 by Materials Project

Th2CeO6 is Fluorite-derived structured and crystallizes in the monoclinic Cm 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 2.41–2.44 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 2.41–2.44 Å. Ce4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Ce–O bond distances ranging from 2.38–2.40 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to three Th4+ and one Ce4+ atom to form a mixture of corner and edge-sharing OCeTh3 tetrahedra. In the second O2- site, O2- is bonded to two Th4+ and two equivalent Ce4+ atoms to form a mixture of corner and edge-sharing OCe2Th2 tetrahedra. In the third O2- site, O2- is bonded to three Th4+ and one Ce4+ atom to form a mixture of corner and edge-sharing OCeTh3 tetrahedra. In the fourth O2- site, O2- is bonded to three Th4+ and one Ce4+ atom to form a mixture of corner and edge-sharing OCeTh3 tetrahedra. In the fifth O2- site, O2- is bonded to two Th4+ and two equivalent Ce4+ atoms to form a mixture of corner and edge-sharing OCe2Th2 tetrahedra. In the sixth O2- site, O2- is bonded to three Th4+ and one Ce4+ atom to form a mixture of corner and edge-sharing OCeTh3 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce4ThO9 by Materials Project

ThCe4O9 crystallizes in the tetragonal I-4 space group. The structure is three-dimensional. Th4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.35 Å) and four longer (2.55 Å) Th–O bond lengths. Ce+3.50+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ce–O bond distances ranging from 2.31–2.44 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Ce+3.50+ atoms to form a mixture of edge and corner-sharing OCe4 tetrahedra. In the second O2- site, O2- is bonded to one Th4+ and three equivalent Ce+3.50+ atoms to form a mixture of edge and corner-sharing OCe3Th tetrahedra. In the third O2- site, O2- is bonded to one Th4+ and three equivalent Ce+3.50+ atoms to form distorted OCe3Th tetrahedra that share corners with fifteen OCe4 tetrahedra and edges with five equivalent OCe3Th tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce3Th2O9 by Materials Project

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 2.37–2.53 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 2.36–2.55 Å. There are three inequivalent Ce+3.33+ sites. In the first 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 2.33–2.51 Å. In the second Ce+3.33+ site, Ce+3.33+ is bonded in a distorted hexagonal planar geometry to six O2- atoms. There are a spread of Ce–O bond distances ranging from 2.31–2.37 Å. In the third 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 2.33–2.50 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 a mixture of distorted edge and corner-sharing OCe3Th tetrahedra. In the second 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 third 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 OCeTh3 tetrahedra. In the fourth 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 fifth 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 sixth O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form a mixture of edge and corner-sharing OCe3Th 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 OCeTh3 tetrahedra. In the eighth O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form a mixture of edge and corner-sharing OCe3Th tetrahedra. In the ninth O2- site, O2- is bonded to four Ce+3.33+ atoms to form a mixture of edge and corner-sharing OCe4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CeTh3O8 by Materials Project

Th3CeO8 is Fluorite-derived structured and crystallizes in the orthorhombic Cmmm 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 six shorter (2.42 Å) and two longer (2.43 Å) Th–O bond lengths. In the second Th4+ site, Th4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.42 Å) and four longer (2.43 Å) Th–O bond lengths. Ce4+ is bonded in a body-centered cubic geometry to eight O2- atoms. All Ce–O bond lengths are 2.40 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four Th4+ atoms to form a mixture of corner and edge-sharing OTh4 tetrahedra. In the second O2- site, O2- is bonded to three Th4+ and one Ce4+ atom to form a mixture of corner and edge-sharing OCeTh3 tetrahedra. In the third O2- site, O2- is bonded to two equivalent Th4+ and two equivalent Ce4+ atoms to form a mixture of corner and edge-sharing OCe2Th2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce4ThO8 by Materials Project

ThCe4O8 crystallizes in the triclinic P1 space group. The structure is three-dimensional. Th4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Th–O bond distances ranging from 2.38–2.47 Å. There are four inequivalent Ce3+ sites. In the first Ce3+ site, Ce3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ce–O bond distances ranging from 2.31–2.51 Å. In the second Ce3+ site, Ce3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ce–O bond distances ranging from 2.25–2.49 Å. In the third Ce3+ site, Ce3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ce–O bond distances ranging from 2.25–2.49 Å. In the fourth Ce3+ site, Ce3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ce–O bond distances ranging from 2.32–2.52 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Th4+ and two equivalent Ce3+ atoms to form a mixture of corner and edge-sharing OCe2Th2 tetrahedra. In the second O2- site, O2- is bonded to two equivalent Th4+ and two equivalent Ce3+ atoms to form a mixture of corner and edge-sharing OCe2Th2 tetrahedra. In the third O2- site, O2- is bonded to four Ce3+ atoms to form OCe4 tetrahedra that share corners with sixteen OCe2Th2 tetrahedra and edges with two OCe4 tetrahedra. In the fourth O2- site, O2- is bonded to four Ce3+ atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra. In the fifth O2- site, O2- is bonded to four Ce3+ atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra. In the sixth O2- site, O2- is bonded to four Ce3+ atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra. In the seventh O2- site, O2- is bonded to two equivalent Th4+ and two equivalent Ce3+ atoms to form a mixture of corner and edge-sharing OCe2Th2 tetrahedra. In the eighth O2- site, O2- is bonded to two equivalent Th4+ and two equivalent Ce3+ atoms to form OCe2Th2 tetrahedra that share corners with fourteen OCe4 tetrahedra and edges with five OCe2Th2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce3Th2O9 by Materials Project

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.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce3Th3O11 by Materials Project

Th3Ce3O11 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are three 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 2.37–2.63 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 2.39–2.55 Å. In the third 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 2.40–2.49 Å. There are three inequivalent Ce+3.33+ sites. In the first Ce+3.33+ site, Ce+3.33+ is bonded to seven O2- atoms to form a mixture of distorted edge and corner-sharing CeO7 hexagonal pyramids. There are a spread of Ce–O bond distances ranging from 2.35–2.47 Å. In the second Ce+3.33+ site, Ce+3.33+ is bonded to seven O2- atoms to form a mixture of distorted edge and corner-sharing CeO7 hexagonal pyramids. There are a spread of Ce–O bond distances ranging from 2.35–2.49 Å. In the third 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 2.29–2.41 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded to three Th4+ and one Ce+3.33+ atom to form OCeTh3 tetrahedra that share corners with fifteen OCeTh3 tetrahedra and edges with six OCe2Th2 tetrahedra. In the second O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form a mixture of edge and corner-sharing OCe3Th 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 OCeTh3 tetrahedra and edges with five OCe2Th2 tetrahedra. In the fourth 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 OCe2Th2 tetrahedra. In the fifth O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form distorted OCe3Th tetrahedra that share corners with sixteen OCeTh3 tetrahedra and edges with four OCe2Th2 tetrahedra. In the sixth 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 seventh O2- site, O2- is bonded to four Th4+ atoms to form OTh4 tetrahedra that share corners with sixteen OCeTh3 tetrahedra and edges with six OCe2Th2 tetrahedra. In the eighth O2- site, O2- is bonded to three Th4+ and one Ce+3.33+ atom to form OCeTh3 tetrahedra that share corners with fifteen OCeTh3 tetrahedra and edges with six OCe3Th tetrahedra. In the ninth O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form distorted OCe3Th tetrahedra that share corners with sixteen OCeTh3 tetrahedra and edges with four OCe3Th tetrahedra. In the tenth 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 eleventh O2- site, O2- is bonded to one Th4+ and three Ce+3.33+ atoms to form a mixture of edge and corner-sharing OCe3Th tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce3Th4O14 by Materials Project

Th4Ce3O14 is Fluorite-derived structured and crystallizes in the monoclinic C2/m 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. All Th–O bond lengths are 2.42 Å. In the second Th4+ site, Th4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are two shorter (2.41 Å) and six longer (2.42 Å) Th–O bond lengths. There are two inequivalent Ce4+ sites. In the first Ce4+ site, Ce4+ is bonded in a body-centered cubic geometry to eight O2- atoms. All Ce–O bond lengths are 2.39 Å. In the second Ce4+ site, Ce4+ is bonded in a body-centered cubic geometry to eight O2- atoms. All Ce–O bond lengths are 2.39 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to three Th4+ and one Ce4+ atom to form a mixture of edge and corner-sharing OCeTh3 tetrahedra. In the second O2- site, O2- is bonded to two equivalent Th4+ and two Ce4+ atoms to form a mixture of edge and corner-sharing OCe2Th2 tetrahedra. In the third O2- site, O2- is bonded to two Th4+ and two Ce4+ atoms to form a mixture of edge and corner-sharing OCe2Th2 tetrahedra. In the fourth O2- site, O2- is bonded to two equivalent Th4+ and two equivalent Ce4+ atoms to form a mixture of edge and corner-sharing OCe2Th2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce4ThO10 by Materials Project

ThCe4O10 is Fluorite-derived structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th4+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Th–O bond lengths are 2.40 Å. There are two inequivalent Ce4+ sites. In the first Ce4+ site, Ce4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.37 Å) and four longer (2.38 Å) Ce–O bond lengths. In the second Ce4+ site, Ce4+ is bonded in a body-centered cubic geometry to eight O2- atoms. All Ce–O bond lengths are 2.37 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four Ce4+ atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra. In the second O2- site, O2- is bonded to two equivalent Th4+ and two equivalent Ce4+ atoms to form a mixture of corner and edge-sharing OCe2Th2 tetrahedra. In the third O2- site, O2- is bonded to four equivalent Ce4+ atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CeTh2O6 by Materials Project

Th2CeO6 is Fluorite-derived structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Th4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are seven shorter (2.42 Å) and one longer (2.45 Å) Th–O bond lengths. Ce4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are two shorter (2.37 Å) and six longer (2.40 Å) Ce–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Th4+ and one Ce4+ atom to form OCeTh3 tetrahedra that share corners with sixteen OCeTh3 tetrahedra and edges with six OCe3Th tetrahedra. In the second O2- site, O2- is bonded to one Th4+ and three equivalent Ce4+ atoms to form a mixture of edge and corner-sharing OCe3Th tetrahedra. In the third O2- site, O2- is bonded to four equivalent Th4+ atoms to form a mixture of edge and corner-sharing OTh4 tetrahedra.

36 MATERIALS SCIENCE↗