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Materials Data on Ca3UO6 by Materials Project

Ca3UO6 is Ilmenite-like structured and crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Ca2+ is bonded to six O2- atoms to form distorted CaO6 pentagonal pyramids that share corners with two UO6 octahedra, corners with four equivalent CaO6 pentagonal pyramids, edges with two UO6 octahedra, and edges with four equivalent CaO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 36–43°. There are a spread of Ca–O bond distances ranging from 2.32–2.52 Å. There are two inequivalent U6+ sites. In the first U6+ site, U6+ is bonded to six equivalent O2- atoms to form UO6 octahedra that share corners with six equivalent CaO6 pentagonal pyramids and edges with six equivalent CaO6 pentagonal pyramids. All U–O bond lengths are 2.10 Å. In the second U6+ site, U6+ is bonded to six equivalent O2- atoms to form UO6 octahedra that share corners with six equivalent CaO6 pentagonal pyramids and edges with six equivalent CaO6 pentagonal pyramids. All U–O bond lengths are 2.10 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Ca2+ and one U6+ atom to form a mixture of distorted corner and edge-sharing OCa3U trigonal pyramids. In the second O2- site, O2- is bonded in a distorted see-saw-like geometry to three equivalent Ca2+ and one U6+ atom.

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Materials Data on Ca2UO5 by Materials Project

Ca2UO5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.32–2.79 Å. In the second Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.28–2.99 Å. There are two inequivalent U6+ sites. In the first U6+ site, U6+ is bonded to six O2- atoms to form corner-sharing UO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of U–O bond distances ranging from 2.03–2.24 Å. In the second U6+ site, U6+ is bonded to six O2- atoms to form corner-sharing UO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of U–O bond distances ranging from 1.98–2.22 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to two Ca2+ and two U6+ atoms to form distorted corner-sharing OCa2U2 tetrahedra. In the second O2- site, O2- is bonded in a 3-coordinate geometry to three Ca2+ and one U6+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one U6+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one U6+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one U6+ atom.

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Materials Data on CaUO4 by Materials Project

CaUO4 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Ca2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are two shorter (2.45 Å) and six longer (2.46 Å) Ca–O bond lengths. U6+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are two shorter (1.99 Å) and six longer (2.31 Å) U–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Ca2+ and one U6+ atom to form a mixture of distorted edge and corner-sharing OCa3U tetrahedra. In the second O2- site, O2- is bonded to one Ca2+ and three equivalent U6+ atoms to form a mixture of distorted edge and corner-sharing OCaU3 tetrahedra.

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Materials Data on Ca3UO6 by Materials Project

Ca3UO6 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.87 Å. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six equivalent UO6 octahedra. The corner-sharing octahedra tilt angles range from 36–45°. There are a spread of Ca–O bond distances ranging from 2.30–2.43 Å. U6+ is bonded to six O2- atoms to form UO6 octahedra that share corners with six equivalent CaO6 octahedra. The corner-sharing octahedra tilt angles range from 36–45°. There are two shorter (2.07 Å) and four longer (2.11 Å) U–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to three Ca2+ and one U6+ atom to form a mixture of distorted corner and edge-sharing OCa3U tetrahedra. In the second O2- site, O2- is bonded in a 5-coordinate geometry to four Ca2+ and one U6+ atom. In the third O2- site, O2- is bonded to three Ca2+ and one U6+ atom to form a mixture of distorted corner and edge-sharing OCa3U trigonal pyramids.

36 MATERIALS SCIENCE↗

Materials Data on CaUO4 by Materials Project

CaUO4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ca2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.17–2.55 Å. U6+ is bonded in a distorted square co-planar geometry to eight O2- atoms. There are a spread of U–O bond distances ranging from 1.97–2.46 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three equivalent Ca2+ and one U6+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Ca2+ and three equivalent U6+ atoms.

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Materials Data on Ca3UO6 by Materials Project

Ca3UO6 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are three inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six equivalent UO6 octahedra. The corner-sharing octahedra tilt angles range from 36–44°. There are a spread of Ca–O bond distances ranging from 2.31–2.39 Å. In the second Ca2+ site, Ca2+ is bonded in a 4-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.94 Å. In the third Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.84 Å. U6+ is bonded to six O2- atoms to form UO6 octahedra that share corners with six equivalent CaO6 octahedra. The corner-sharing octahedra tilt angles range from 36–44°. There are a spread of U–O bond distances ranging from 2.07–2.12 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to three Ca2+ and one U6+ atom to form distorted corner-sharing OCa3U trigonal pyramids. In the second O2- site, O2- is bonded in a 3-coordinate geometry to four Ca2+ and one U6+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one U6+ atom. In the fourth O2- site, O2- is bonded to three Ca2+ and one U6+ atom to form distorted corner-sharing OCa3U tetrahedra. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to four Ca2+ and one U6+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one U6+ atom.

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