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Materials Data on CeSe2 by Materials Project

CeSe2 is quartz (alpha)-like structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are eight inequivalent Ce4+ sites. In the first Ce4+ site, Ce4+ is bonded to four Se2- atoms to form corner-sharing CeSe4 tetrahedra. There are two shorter (2.73 Å) and two longer (2.74 Å) Ce–Se bond lengths. In the second Ce4+ site, Ce4+ is bonded to four Se2- atoms to form corner-sharing CeSe4 tetrahedra. There are two shorter (2.73 Å) and two longer (2.74 Å) Ce–Se bond lengths. In the third Ce4+ site, Ce4+ is bonded to four Se2- atoms to form corner-sharing CeSe4 tetrahedra. There are two shorter (2.73 Å) and two longer (2.74 Å) Ce–Se bond lengths. In the fourth Ce4+ site, Ce4+ is bonded to four Se2- atoms to form corner-sharing CeSe4 tetrahedra. There are two shorter (2.73 Å) and two longer (2.74 Å) Ce–Se bond lengths. In the fifth Ce4+ site, Ce4+ is bonded to four Se2- atoms to form corner-sharing CeSe4 tetrahedra. There are one shorter (2.73 Å) and three longer (2.74 Å) Ce–Se bond lengths. In the sixth Ce4+ site, Ce4+ is bonded to four Se2- atoms to form corner-sharing CeSe4 tetrahedra. There are two shorter (2.73 Å) and two longer (2.74 Å) Ce–Se bond lengths. In the seventh Ce4+ site, Ce4+ is bonded to four Se2- atoms to form corner-sharing CeSe4 tetrahedra. There are two shorter (2.73 Å) and two longer (2.74 Å) Ce–Se bond lengths. In the eighth Ce4+ site, Ce4+ is bonded to four Se2- atoms to form corner-sharing CeSe4 tetrahedra. There are three shorter (2.73 Å) and one longer (2.74 Å) Ce–Se bond lengths. There are sixteen inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted bent 150 degrees geometry to two Ce4+ atoms. In the second Se2- site, Se2- is bonded in a distorted bent 150 degrees geometry to two Ce4+ atoms. In the third Se2- site, Se2- is bonded in a distorted bent 150 degrees geometry to two Ce4+ atoms. In the fourth Se2- site, Se2- is bonded in a distorted bent 150 degrees geometry to two Ce4+ atoms. In the fifth Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms. In the sixth Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms. In the seventh Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms. In the eighth Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms. In the ninth Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms. In the tenth Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms. In the eleventh Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms. In the twelfth Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms. In the thirteenth Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms. In the fourteenth Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms. In the fifteenth Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms. In the sixteenth Se2- site, Se2- is bonded in a bent 150 degrees geometry to two Ce4+ atoms.

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Materials Data on CeMg2 by Materials Project

CeMg2 is Magnesium-derived structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to six Mg and six equivalent Ce atoms to form MgCe6Mg6 cuboctahedra that share corners with six equivalent CeCe4Mg8 cuboctahedra, corners with twelve MgCe6Mg6 cuboctahedra, edges with seven equivalent CeCe4Mg8 cuboctahedra, edges with eleven MgCe6Mg6 cuboctahedra, faces with six equivalent CeCe4Mg8 cuboctahedra, and faces with fourteen MgCe6Mg6 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.09–3.21 Å. There are two shorter (3.34 Å) and four longer (3.43 Å) Mg–Ce bond lengths. In the second Mg site, Mg is bonded to ten Mg and two equivalent Ce atoms to form MgCe2Mg10 cuboctahedra that share corners with six equivalent CeCe4Mg8 cuboctahedra, corners with twelve MgCe6Mg6 cuboctahedra, edges with seven MgCe6Mg6 cuboctahedra, edges with eleven equivalent CeCe4Mg8 cuboctahedra, faces with four equivalent CeCe4Mg8 cuboctahedra, and faces with sixteen MgCe6Mg6 cuboctahedra. There are two shorter (3.20 Å) and four longer (3.26 Å) Mg–Mg bond lengths. Both Mg–Ce bond lengths are 3.59 Å. Ce is bonded to eight Mg and four equivalent Ce atoms to form CeCe4Mg8 cuboctahedra that share corners with six equivalent CeCe4Mg8 cuboctahedra, corners with twelve MgCe6Mg6 cuboctahedra, edges with eighteen MgCe6Mg6 cuboctahedra, faces with ten MgCe6Mg6 cuboctahedra, and faces with ten equivalent CeCe4Mg8 cuboctahedra. There are two shorter (2.95 Å) and two longer (3.20 Å) Ce–Ce bond lengths.

36 MATERIALS SCIENCE↗
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Materials Data on CeMg2 by Materials Project

CeMg2 is Magnesium-derived structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to eight Mg and four equivalent Ce atoms to form MgCe4Mg8 cuboctahedra that share corners with six equivalent CeCe6Mg6 cuboctahedra, corners with twelve MgCe4Mg8 cuboctahedra, edges with three equivalent CeCe6Mg6 cuboctahedra, edges with fifteen MgCe4Mg8 cuboctahedra, faces with eight equivalent CeCe6Mg6 cuboctahedra, and faces with twelve MgCe4Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.14–3.22 Å. There are two shorter (3.35 Å) and two longer (3.40 Å) Mg–Ce bond lengths. In the second Mg site, Mg is bonded to ten Mg and two equivalent Ce atoms to form MgCe2Mg10 cuboctahedra that share corners with six equivalent CeCe6Mg6 cuboctahedra, corners with twelve MgCe4Mg8 cuboctahedra, edges with seven equivalent MgCe4Mg8 cuboctahedra, edges with eleven equivalent CeCe6Mg6 cuboctahedra, faces with four equivalent CeCe6Mg6 cuboctahedra, and faces with sixteen MgCe4Mg8 cuboctahedra. There are two shorter (3.14 Å) and two longer (3.20 Å) Mg–Mg bond lengths. Both Mg–Ce bond lengths are 3.51 Å. Ce is bonded to six Mg and six equivalent Ce atoms to form CeCe6Mg6 cuboctahedra that share corners with six equivalent CeCe6Mg6 cuboctahedra, corners with twelve MgCe4Mg8 cuboctahedra, edges with four equivalent CeCe6Mg6 cuboctahedra, edges with fourteen MgCe4Mg8 cuboctahedra, faces with eight equivalent CeCe6Mg6 cuboctahedra, and faces with twelve MgCe4Mg8 cuboctahedra. There are four shorter (3.11 Å) and two longer (3.14 Å) Ce–Ce bond lengths.

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Materials Data on CeCu6(PO7)3 by Materials Project

(CeCu6(PO6)3)2(O2)3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional and consists of two trioxirane molecules and one CeCu6(PO6)3 framework. In the CeCu6(PO6)3 framework, Ce is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Ce–O bond distances ranging from 2.39–2.53 Å. There are three inequivalent Cu sites. In the first Cu site, Cu is bonded to five O atoms to form distorted CuO5 square pyramids that share corners with three PO4 tetrahedra and edges with two equivalent CuO5 square pyramids. There are a spread of Cu–O bond distances ranging from 1.82–2.44 Å. In the second Cu site, Cu is bonded to five O atoms to form distorted CuO5 square pyramids that share corners with three PO4 tetrahedra and edges with two equivalent CuO5 square pyramids. There are a spread of Cu–O bond distances ranging from 1.82–2.42 Å. In the third Cu site, Cu is bonded to five O atoms to form distorted CuO5 square pyramids that share corners with three PO4 tetrahedra and edges with two equivalent CuO5 square pyramids. There are a spread of Cu–O bond distances ranging from 1.82–2.43 Å. There are three inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with six CuO5 square pyramids. There are a spread of P–O bond distances ranging from 1.52–1.60 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with six CuO5 square pyramids. There are a spread of P–O bond distances ranging from 1.52–1.60 Å. In the third P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with six CuO5 square pyramids. There are a spread of P–O bond distances ranging from 1.52–1.60 Å. There are fifteen inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the second O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the third O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the fourth O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the fifth O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the sixth O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the seventh O site, O is bonded in a 1-coordinate geometry to one Ce, one Cu, and one P atom. In the eighth O site, O is bonded in a distorted single-bond geometry to one Ce, one Cu, and one P atom. In the ninth O site, O is bonded in a distorted single-bond geometry to one Ce, one Cu, and one P atom. In the tenth O site, O is bonded in a water-like geometry to two equivalent Cu atoms. In the eleventh O site, O is bonded in a water-like geometry to two equivalent Cu atoms. In the twelfth O site, O is bonded in a water-like geometry to two equivalent Cu atoms. In the thirteenth O site, O is bonded in a trigonal non-coplanar geometry to one Ce and two equivalent Cu atoms. In the fourteenth O site, O is bonded in a trigonal non-coplanar geometry to one Ce and two equivalent Cu atoms. In the fifteenth O site, O is bonded in a trigonal non-coplanar geometry to one Ce and two equivalent Cu atoms.

36 MATERIALS SCIENCE↗
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Materials Data on Ce3Si2 by Materials Project

Ce3Si2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. there are two inequivalent Ce sites. In the first Ce site, Ce is bonded in a square co-planar geometry to four equivalent Si atoms. All Ce–Si bond lengths are 3.08 Å. In the second Ce site, Ce is bonded in a distorted hexagonal planar geometry to six equivalent Si atoms. There are two shorter (3.05 Å) and four longer (3.10 Å) Ce–Si bond lengths. Si is bonded in a 9-coordinate geometry to eight Ce and one Si atom. The Si–Si bond length is 2.46 Å.

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Materials Data on CeMg2 by Materials Project

CeMg2 crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to eight Mg and four equivalent Ce atoms to form MgCe4Mg8 cuboctahedra that share corners with eighteen equivalent MgCe4Mg8 cuboctahedra, edges with eight equivalent CeCe3Mg9 cuboctahedra, edges with ten MgCe4Mg8 cuboctahedra, faces with eight equivalent CeCe3Mg9 cuboctahedra, and faces with twelve MgCe4Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.30–3.41 Å. All Mg–Ce bond lengths are 3.39 Å. In the second Mg site, Mg is bonded to six equivalent Mg and six equivalent Ce atoms to form MgCe6Mg6 cuboctahedra that share corners with eighteen equivalent CeCe3Mg9 cuboctahedra, edges with eighteen MgCe4Mg8 cuboctahedra, faces with six equivalent CeCe3Mg9 cuboctahedra, and faces with fourteen MgCe4Mg8 cuboctahedra. All Mg–Ce bond lengths are 3.37 Å. Ce is bonded to nine Mg and three equivalent Ce atoms to form CeCe3Mg9 cuboctahedra that share corners with nine equivalent MgCe6Mg6 cuboctahedra, corners with nine equivalent CeCe3Mg9 cuboctahedra, edges with six equivalent CeCe3Mg9 cuboctahedra, edges with twelve equivalent MgCe4Mg8 cuboctahedra, faces with five equivalent CeCe3Mg9 cuboctahedra, and faces with fifteen MgCe4Mg8 cuboctahedra. All Ce–Ce bond lengths are 3.37 Å.

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Materials Data on Ce5Sn3 by Materials Project

Ce5Sn3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Ce sites. In the first Ce site, Ce is bonded in a 6-coordinate geometry to six equivalent Sn atoms. All Ce–Sn bond lengths are 3.31 Å. In the second Ce site, Ce is bonded in a 5-coordinate geometry to five equivalent Sn atoms. There are a spread of Ce–Sn bond distances ranging from 3.20–3.48 Å. Sn is bonded in a 9-coordinate geometry to nine Ce atoms.

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Materials Data on Ce2(SO6)3 by Materials Project

Ce2(SO6)3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Ce is bonded in a 1-coordinate geometry to six O atoms. There are a spread of Ce–O bond distances ranging from 1.88–2.42 Å. There are two inequivalent S sites. In the first S site, S is bonded in a tetrahedral geometry to four O atoms. There are a spread of S–O bond distances ranging from 1.48–1.50 Å. In the second S site, S is bonded in a tetrahedral geometry to four O atoms. There is two shorter (1.45 Å) and two longer (1.52 Å) S–O bond length. There are nine inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Ce and one S atom. In the second O site, O is bonded in a single-bond geometry to one S atom. In the third O site, O is bonded in a distorted linear geometry to one Ce and one S atom. In the fourth O site, O is bonded in a water-like geometry to one Ce and one O atom. The O–O bond length is 1.81 Å. In the fifth O site, O is bonded in a single-bond geometry to one Ce atom. In the sixth O site, O is bonded in a distorted linear geometry to one Ce and one S atom. In the seventh O site, O is bonded in a 2-coordinate geometry to two O atoms. The O–O bond length is 1.26 Å. In the eighth O site, O is bonded in a distorted bent 120 degrees geometry to one Ce and one S atom. In the ninth O site, O is bonded in a single-bond geometry to one S atom.

36 MATERIALS SCIENCE↗
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Materials Data on Ce5Sb4As by Materials Project

Ce5Sb4As is Caswellsilverite-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are five inequivalent Ce3+ sites. In the first Ce3+ site, Ce3+ is bonded to six Sb3- atoms to form a mixture of edge and corner-sharing CeSb6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Ce–Sb bond distances ranging from 3.14–3.17 Å. In the second Ce3+ site, Ce3+ is bonded to five Sb3- and one As3- atom to form CeSb5As octahedra that share corners with six CeSb6 octahedra and edges with twelve CeSb5As octahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are four shorter (3.15 Å) and one longer (3.22 Å) Ce–Sb bond lengths. The Ce–As bond length is 2.99 Å. In the third Ce3+ site, Ce3+ is bonded to two equivalent Sb3- and four equivalent As3- atoms to form CeSb2As4 octahedra that share corners with six CeSb6 octahedra and edges with twelve CeSb5As octahedra. The corner-sharing octahedral tilt angles are 0°. Both Ce–Sb bond lengths are 3.12 Å. All Ce–As bond lengths are 3.15 Å. In the fourth Ce3+ site, Ce3+ is bonded to six Sb3- atoms to form CeSb6 octahedra that share corners with six CeSb5As octahedra and edges with twelve CeSb6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Ce–Sb bond distances ranging from 3.14–3.17 Å. In the fifth Ce3+ site, Ce3+ is bonded to five Sb3- and one As3- atom to form CeSb5As octahedra that share corners with six CeSb5As octahedra and edges with twelve CeSb6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are four shorter (3.15 Å) and one longer (3.22 Å) Ce–Sb bond lengths. The Ce–As bond length is 2.99 Å. There are two inequivalent Sb3- sites. In the first Sb3- site, Sb3- is bonded to six Ce3+ atoms to form SbCe6 octahedra that share corners with six SbCe6 octahedra, edges with four equivalent AsCe6 octahedra, and edges with eight SbCe6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the second Sb3- site, Sb3- is bonded to six Ce3+ atoms to form SbCe6 octahedra that share a cornercorner with one AsCe6 octahedra, corners with five SbCe6 octahedra, and edges with twelve SbCe6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. As3- is bonded to six Ce3+ atoms to form AsCe6 octahedra that share corners with two equivalent SbCe6 octahedra, corners with four equivalent AsCe6 octahedra, edges with four equivalent AsCe6 octahedra, and edges with eight equivalent SbCe6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
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Materials Data on CeCu6(PO7)3 by Materials Project

(CeCu6(PO6)3)2(O2)3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional and consists of two trioxirane molecules and one CeCu6(PO6)3 framework. In the CeCu6(PO6)3 framework, Ce is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Ce–O bond distances ranging from 2.41–2.51 Å. There are three inequivalent Cu sites. In the first Cu site, Cu is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Cu–O bond distances ranging from 1.82–2.59 Å. In the second Cu site, Cu is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Cu–O bond distances ranging from 1.82–2.57 Å. In the third Cu site, Cu is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Cu–O bond distances ranging from 1.82–2.56 Å. There are three inequivalent P sites. In the first P site, P is bonded in a tetrahedral geometry to four O atoms. There are a spread of P–O bond distances ranging from 1.52–1.60 Å. In the second P site, P is bonded in a tetrahedral geometry to four O atoms. There are a spread of P–O bond distances ranging from 1.51–1.60 Å. In the third P site, P is bonded in a tetrahedral geometry to four O atoms. There are a spread of P–O bond distances ranging from 1.51–1.60 Å. There are fifteen inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the second O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the third O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the fourth O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the fifth O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the sixth O site, O is bonded in a distorted trigonal planar geometry to two equivalent Cu and one P atom. In the seventh O site, O is bonded in a 1-coordinate geometry to one Ce, one Cu, and one P atom. In the eighth O site, O is bonded in a distorted single-bond geometry to one Ce, one Cu, and one P atom. In the ninth O site, O is bonded in a distorted single-bond geometry to one Ce, one Cu, and one P atom. In the tenth O site, O is bonded in a water-like geometry to two equivalent Cu atoms. In the eleventh O site, O is bonded in a water-like geometry to two equivalent Cu atoms. In the twelfth O site, O is bonded in a water-like geometry to two equivalent Cu atoms. In the thirteenth O site, O is bonded in a distorted trigonal non-coplanar geometry to one Ce and two equivalent Cu atoms. In the fourteenth O site, O is bonded in a trigonal non-coplanar geometry to one Ce and two equivalent Cu atoms. In the fifteenth O site, O is bonded in a distorted trigonal non-coplanar geometry to one Ce and two equivalent Cu atoms.

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Materials Data on CeMg2 by Materials Project

CeMg2 is beta-derived structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to six Mg and six equivalent Ce atoms to form MgCe6Mg6 cuboctahedra that share corners with six equivalent CeCe2Mg10 cuboctahedra, corners with twelve MgCe6Mg6 cuboctahedra, edges with seven equivalent CeCe2Mg10 cuboctahedra, edges with eleven equivalent MgCe4Mg8 cuboctahedra, faces with six equivalent CeCe2Mg10 cuboctahedra, and faces with fourteen MgCe6Mg6 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.19–3.41 Å. There are four shorter (3.34 Å) and two longer (3.36 Å) Mg–Ce bond lengths. In the second Mg site, Mg is bonded to eight Mg and four equivalent Ce atoms to form MgCe4Mg8 cuboctahedra that share corners with six equivalent CeCe2Mg10 cuboctahedra, corners with twelve MgCe6Mg6 cuboctahedra, edges with three equivalent CeCe2Mg10 cuboctahedra, edges with fifteen MgCe6Mg6 cuboctahedra, faces with eight equivalent CeCe2Mg10 cuboctahedra, and faces with twelve MgCe6Mg6 cuboctahedra. There are two shorter (3.19 Å) and four longer (3.38 Å) Mg–Mg bond lengths. There are two shorter (3.38 Å) and two longer (3.42 Å) Mg–Ce bond lengths. Ce is bonded to ten Mg and two equivalent Ce atoms to form CeCe2Mg10 cuboctahedra that share corners with six equivalent CeCe2Mg10 cuboctahedra, corners with twelve MgCe6Mg6 cuboctahedra, edges with eight equivalent CeCe2Mg10 cuboctahedra, edges with ten MgCe6Mg6 cuboctahedra, faces with six equivalent CeCe2Mg10 cuboctahedra, and faces with fourteen MgCe6Mg6 cuboctahedra. Both Ce–Ce bond lengths are 3.19 Å.

36 MATERIALS SCIENCE↗
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Materials Data on Ce4Ga2S5O4 by Materials Project

(CeO)4Ga2S5 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Ce3+ sites. In the first Ce3+ site, Ce3+ is bonded in a 4-coordinate geometry to three S2- and four O2- atoms. There are two shorter (3.07 Å) and one longer (3.28 Å) Ce–S bond lengths. There are a spread of Ce–O bond distances ranging from 2.32–2.39 Å. In the second Ce3+ site, Ce3+ is bonded in a 4-coordinate geometry to four S2- and four O2- atoms. There are a spread of Ce–S bond distances ranging from 2.98–3.02 Å. There are a spread of Ce–O bond distances ranging from 2.30–2.36 Å. In the third Ce3+ site, Ce3+ is bonded in a 4-coordinate geometry to three S2- and four O2- atoms. There are two shorter (3.05 Å) and one longer (3.37 Å) Ce–S bond lengths. There are a spread of Ce–O bond distances ranging from 2.33–2.35 Å. In the fourth Ce3+ site, Ce3+ is bonded in a 4-coordinate geometry to four S2- and four O2- atoms. There are a spread of Ce–S bond distances ranging from 2.96–3.03 Å. There are a spread of Ce–O bond distances ranging from 2.33–2.38 Å. There are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four S2- atoms to form corner-sharing GaS4 tetrahedra. There are a spread of Ga–S bond distances ranging from 2.25–2.35 Å. In the second Ga3+ site, Ga3+ is bonded in a distorted trigonal non-coplanar geometry to three S2- atoms. There are a spread of Ga–S bond distances ranging from 2.55–2.64 Å. There are five inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to four Ce3+ and one Ga3+ atom. In the second S2- site, S2- is bonded in a 1-coordinate geometry to two equivalent Ce3+ and one Ga3+ atom. In the third S2- site, S2- is bonded in a 1-coordinate geometry to two equivalent Ce3+ and one Ga3+ atom. In the fourth S2- site, S2- is bonded in a 1-coordinate geometry to four Ce3+ and one Ga3+ atom. In the fifth S2- site, S2- is bonded in a 5-coordinate geometry to two Ce3+ and three Ga3+ atoms. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four Ce3+ atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra. In the second O2- site, O2- is bonded to four Ce3+ atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra. In the third O2- site, O2- is bonded to four Ce3+ atoms to form a mixture of corner and edge-sharing 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.

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Materials Data on CeMnAl by Materials Project

CeMnAl is Cubic Laves-derived structured and crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Ce is bonded in a 12-coordinate geometry to four equivalent Ce, six equivalent Mn, and six equivalent Al atoms. There are two shorter (3.21 Å) and two longer (3.46 Å) Ce–Ce bond lengths. There are two shorter (3.05 Å) and four longer (3.24 Å) Ce–Mn bond lengths. There are four shorter (3.19 Å) and two longer (3.24 Å) Ce–Al bond lengths. Mn is bonded to six equivalent Ce, two equivalent Mn, and four equivalent Al atoms to form MnCe6Mn2Al4 cuboctahedra that share corners with eight equivalent AlCe6Mn4Al2 cuboctahedra, corners with ten equivalent MnCe6Mn2Al4 cuboctahedra, edges with six equivalent MnCe6Mn2Al4 cuboctahedra, faces with six equivalent MnCe6Mn2Al4 cuboctahedra, and faces with twelve equivalent AlCe6Mn4Al2 cuboctahedra. Both Mn–Mn bond lengths are 2.76 Å. All Mn–Al bond lengths are 2.71 Å. Al is bonded to six equivalent Ce, four equivalent Mn, and two equivalent Al atoms to form AlCe6Mn4Al2 cuboctahedra that share corners with eight equivalent MnCe6Mn2Al4 cuboctahedra, corners with ten equivalent AlCe6Mn4Al2 cuboctahedra, edges with six equivalent AlCe6Mn4Al2 cuboctahedra, faces with six equivalent AlCe6Mn4Al2 cuboctahedra, and faces with twelve equivalent MnCe6Mn2Al4 cuboctahedra. Both Al–Al bond lengths are 2.74 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CeAl(CuNi)2 by Materials Project

CeAl(NiCu)2 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Ce is bonded in a 6-coordinate geometry to eight equivalent Ni, seven Cu, and three equivalent Al atoms. There are four shorter (3.22 Å) and four longer (3.28 Å) Ce–Ni bond lengths. There are a spread of Ce–Cu bond distances ranging from 2.94–3.26 Å. There are one shorter (2.95 Å) and two longer (3.00 Å) Ce–Al bond lengths. Ni is bonded to four equivalent Ce, two equivalent Ni, four Cu, and two equivalent Al atoms to form distorted NiCe4Al2Cu4Ni2 cuboctahedra that share corners with eight CuCe3Al3Cu2Ni4 cuboctahedra, corners with twelve equivalent NiCe4Al2Cu4Ni2 cuboctahedra, edges with four equivalent CuCe4Al2Cu2Ni4 cuboctahedra, edges with six equivalent NiCe4Al2Cu4Ni2 cuboctahedra, faces with six equivalent NiCe4Al2Cu4Ni2 cuboctahedra, and faces with ten CuCe3Al3Cu2Ni4 cuboctahedra. There are one shorter (2.58 Å) and one longer (2.60 Å) Ni–Ni bond lengths. There are a spread of Ni–Cu bond distances ranging from 2.48–2.58 Å. Both Ni–Al bond lengths are 2.47 Å. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded to three equivalent Ce, four equivalent Ni, two equivalent Cu, and three equivalent Al atoms to form distorted CuCe3Al3Cu2Ni4 cuboctahedra that share corners with four equivalent CuCe4Al2Cu2Ni4 cuboctahedra, corners with eight equivalent NiCe4Al2Cu4Ni2 cuboctahedra, edges with six equivalent CuCe3Al3Cu2Ni4 cuboctahedra, faces with eight CuCe3Al3Cu2Ni4 cuboctahedra, and faces with twelve equivalent NiCe4Al2Cu4Ni2 cuboctahedra. Both Cu–Cu bond lengths are 2.47 Å. There are two shorter (2.96 Å) and one longer (3.03 Å) Cu–Al bond lengths. In the second Cu site, Cu is bonded to four equivalent Ce, four equivalent Ni, two equivalent Cu, and two equivalent Al atoms to form distorted CuCe4Al2Cu2Ni4 cuboctahedra that share corners with eight equivalent NiCe4Al2Cu4Ni2 cuboctahedra, corners with twelve CuCe3Al3Cu2Ni4 cuboctahedra, edges with two equivalent CuCe4Al2Cu2Ni4 cuboctahedra, edges with eight equivalent NiCe4Al2Cu4Ni2 cuboctahedra, faces with eight equivalent NiCe4Al2Cu4Ni2 cuboctahedra, and faces with eight CuCe3Al3Cu2Ni4 cuboctahedra. Both Cu–Al bond lengths are 2.52 Å. Al is bonded in a 12-coordinate geometry to three equivalent Ce, four equivalent Ni, and five Cu atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce2Ge5Ir3 by Materials Project

Ce2Ir3Ge5 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. Ce is bonded in a 1-coordinate geometry to seven Ir and ten Ge atoms. There are a spread of Ce–Ir bond distances ranging from 3.14–3.57 Å. There are a spread of Ce–Ge bond distances ranging from 3.01–3.36 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 6-coordinate geometry to four equivalent Ce and six Ge atoms. There are four shorter (2.54 Å) and two longer (2.65 Å) Ir–Ge bond lengths. In the second Ir site, Ir is bonded in a 10-coordinate geometry to five equivalent Ce and five Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.41–2.54 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to four equivalent Ce and four equivalent Ir atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent Ce, three Ir, and two equivalent Ge atoms. Both Ge–Ge bond lengths are 2.69 Å. In the third Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent Ce, three Ir, and two equivalent Ge atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Vacancy Mediated Electrooxidation of 5‐Hydroxymethyl Furfuryl Using Defect Engineered Layered Double Hydroxide Electrocatalysts

Abstract Electrochemical biomass oxidation coupled with hydrogen evolution offers a promising route to generate value‐added chemicals and clean energy. The complex adsorption behavior of 5‐hydroxymethyl furfural (HMF) and hydroxyl ions (OH − ) on the electrocatalyst surface during HMF electrooxidation reaction (HMFOR) necessitates an in‐depth understanding of active sites available for adsorption. Herein, oxygen vacancy (V O ) defects are introduced in NiFe layered double hydroxide (LDH) using Ce dopants to manipulate electronic structure. Synchrotron‐based HE‐XRD and XAS indicate negligible V O in La‐doped NiFe while Ce doping leads to V O defects due to flexible Ce redox (Ce 3+ ↔ Ce 4+ ). The V O ‐rich Ce‐NiFe exhibits higher Faradic efficiency of ≈90% to produce 2,5‐furan dicarboxylic acid (FDCA), far greater than ≈60% for NiFe V O in Ce‐NiFe act as alternative active sites for OH − adsorption, hence reducing adsorption competition for the same metal sites. DFT calculation results corroborate experimental findings by showcasing that the presence of V O in Ce‐NiFe manipulates the adsorption energies and facilitates the chemical adsorption OH − in V O to improve HMFOR. In situ HE‐XRD derived pair distribution function coupled to RMC simulations confirm OH − trapping in V O and HMF adsorption on metal centers as evident by interlayer distance evolution. Taken together, this work showcases routes for dual‐site electrocatalyst design for improved biomass electrooxidation.

Chemistry↗
DOE OSTI2024

Plutonium and Cerium Perrhenate/Pertechnetate Coordination Polymers and Frameworks

Spent nuclear fuel (SNF) contains transuranic and lanthanide species, which are sometimes recovered and repurposed. One particularly problematic fission product, 99 TcO 4 – , hampers this recovery via coextraction with high valence metals, perhaps by complexation during aqueous reprocessing of SNF. There is limited molecular-level knowledge concerning the coordination chemistry between TcO 4 – or its well-known surrogate ReO 4 – and transuranic/lanthanide species. In the current study, we investigated the coordination of ReO 4 – /TcO 4 – with plutonium and cerium cations by structural and chemical characterization of a series of isolated extended solids. In this study, Ce represents both trivalent lanthanides and is considered a surrogate for Pu, respectively, in its common trivalent and tetravalent oxidation states. The structural elucidation of the seven isolated crystalline solids revealed that ReO 4 – /TcO 4 – directly connects to Pu IV , Pu VI O 2 2 + , Ce III , and Ce IV in the terminal and bridging coordination modes, leading to 1-, 2-, and 3-dimensional frameworks. For example, ReO 4 – coordination to Pu(IV) formed a 1D chain or 2D framework, isostructural with previously isolated Th(IV) compounds. However, Pu VI O 2 2 + alternating with ReO 4 – led to a unique 1D chain, different from the prior-reported U(VI)/Np(VI)-ReO 4 – /TcO 4 – structures. Coordination of ReO 4 – /TcO 4 – with Ce(III) promotes the assembly of 3D frameworks. Finally, attempted synthesis of a Ce(IV)-ReO 4 – compound resulted in a 2D framework with a mixed-valence Ce III/IV . The highly acidic reaction conditions supported the reduction of both Ce IV and Tc VII , challenging isolation of compounds featuring these species. Only one TcO 4 -containing structure was obtained in this study (Ce III –TcO 4 3D framework), vs the six total Ce/Pu-ReO 4 compounds. Furthermore, our three Pu-ReO 4 crystal structures are the first reported and translated to atomic-level information about Pu-TcO 4 coordination in nuclear fuel reprocessing scenarios, in addition to broadening our knowledge of bonding trends in the early, high-valence actinides.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2021

High-Temperature-Performance Cyanate Ester Composites with Carboranes

Cyanate ester (CE) is an important class of materials among high-temperature performance thermosets. It is used in aerospace launch vehicles, heat sinks, booms, and trusses of satellites etc. due to its high glass transition temperatures (>220°C), excellent thermal stability, and low flammability. Current approaches to improve the thermal stability of CE include incorporation of siloxanes or phosphorus- based flame retardants (PFRs). In this work, we have explored boron-based hydroxy (PD) and epoxy (EP) functionalized carborane additives to improve the thermal properties of CE. Carborane fillers were solvent blended at various mass loadings in the resin and cured to study their effect on thermal properties. PD and EP carboranes react with CE to form iminocarbonate and oxazolidinone linkages respectively. Cure kinetics studies at different wt% loadings explained that carboranes catalyze the curing reaction by reducing curing activation energy by about 54% and 26% for 10 wt% loadings of PD and EP carboranes respectively. In addition, carborane-filled cyanate ester (CE) nanocomposites demonstrate an exceptionally high thermal stability as compared to the pristine resin in air and inert environment. Our thermogravimetric analysis (TGA) experiments show that the ultimate char yield of the resin can be increased from 0% to as high as 76% and 82% with 30 wt% PD and EP carborane loading respectively at 1000 °C in air. The initial degradation temperature T d;5 of the composites decreased with increasing carborane loadings in both air and argon. For instance, T d;5 for CE was 465 and 471.6 °C in argon and air while that for P20 was 437.4 and 452.1 °C. Modulated TGA studies gave evidence of the effect of carboranes on degradation kinetics and the mechanism of the resin in air and inert environment. The effect of bonding between carboranes and CE at various loadings on the thermal expansion of the matrix was also studied using Thermomechanical Analyzer (TMA). PD carborane reduced the T g for P20 to about 225 °C while CE had T g >350 °C.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗