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DOE OSTI · 1667249

Materials Data on Rb2Th(Si2O5)3 by Materials Project

Abstract

Rb2Th(Si2O5)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Rb–O bond distances ranging from 2.87–3.36 Å. In the second Rb1+ site, Rb1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Rb–O bond distances ranging from 2.93–3.43 Å. In the third Rb1+ site, Rb1+ is bonded to eight O2- atoms to form distorted RbO8 hexagonal bipyramids that share corners with nine SiO4 tetrahedra, an edgeedge with one ThO6 octahedra, an edgeedge with one SiO4 tetrahedra, and a faceface with one ThO6 octahedra. There are a spread of Rb–O bond distances ranging from 3.01–3.44 Å. In the fourth Rb1+ site, Rb1+ is bonded to eight O2- atoms to form distorted RbO8 hexagonal bipyramids that share corners with six SiO4 tetrahedra, edges with two equivalent ThO6 octahedra, and edges with three SiO4 tetrahedra. There are a spread of Rb–O bond distances ranging from 3.10–3.40 Å. There are two inequivalent Th4+ sites. In the first Th4+ site, Th4+ is bonded to six O2- atoms to form distorted ThO6 octahedra that share corners with six SiO4 tetrahedra and edges with two equivalent RbO8 hexagonal bipyramids. There are a spread of Th–O bond distances ranging from 2.31–2.37 Å. In the second Th4+ site, Th4+ is bonded to six O2- atoms to form ThO6 octahedra that share corners with six SiO4 tetrahedra, an edgeedge with one RbO8 hexagonal bipyramid, and a faceface with one RbO8 hexagonal bipyramid. There are a spread of Th–O bond distances ranging from 2.29–2.37 Å. There are twelve inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one ThO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. There are a spread of Si–O bond distances ranging from 1.61–1.65 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one RbO8 hexagonal bipyramid, a cornercorner with one ThO6 octahedra, corners with three SiO4 tetrahedra, and an edgeedge with one RbO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 45°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one RbO8 hexagonal bipyramid, a cornercorner with one ThO6 octahedra, corners with three SiO4 tetrahedra, and an edgeedge with one RbO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 45°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two RbO8 hexagonal bipyramids, a cornercorner with one ThO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one ThO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 31°. There are a spread of Si–O bond distances ranging from 1.60–1.66 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two RbO8 hexagonal bipyramids, a cornercorner with one ThO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. There are a spread of Si–O bond distances ranging from 1.61–1.65 Å. In the seventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent RbO8 hexagonal bipyramids, a cornercorner with one ThO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 21°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the eighth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one RbO8 hexagonal bipyramid, a cornercorner with one ThO6 octahedra, corners with three SiO4 tetrahedra, and an edgeedge with one RbO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 38°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the ninth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two RbO8 hexagonal bipyramids, a cornercorner with one ThO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. There are a spread of Si–O bond distances ranging from 1.61–1.65 Å. In the tenth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent RbO8 hexagonal bipyramids, a cornercorner with one ThO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 35°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the eleventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one RbO8 hexagonal bipyramid, a cornercorner with one ThO6 octahedra, corners with three SiO4 tetrahedra, and an edgeedge with one RbO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 41°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the twelfth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one RbO8 hexagonal bipyramid, a cornercorner with one ThO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 66°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. There are thirty inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Rb1+, one Th4+, and one Si4+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Rb1+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two Rb1+, one Th4+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Rb1+ and two Si4+ atoms. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Rb1+ and two Si4+ atoms. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Rb1+, one Th4+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Rb1+ and two Si4+ atoms. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to two Rb1+, one Th4+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Rb1+ and two Si4+ atoms. In the eleventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Rb1+ and two Si4+ atoms. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one Th4+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Rb1+ and two Si4+ atoms. In the fifteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Rb1+, one Th4+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+ and two Si4+ atoms. In the seventeenth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the eighteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one Th4+, and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+ and two Si4+ atoms. In the twentieth O2- site, O2- is bonded in a 2-coordinate geometry to two Rb1+, one Th4+, and one Si4+ atom. In the twenty-first O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the twenty-second O2- site, O2- is bonded in a 1-coordinate geometry to two Rb1+, one Th4+, and one Si4+ atom. In the twenty-third O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the twenty-fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Rb1+ and two Si4+ atoms. In the twenty-fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one Th4+, and one Si4+ atom. In the twenty-sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Rb1+ and two Si4+ atoms. In the twenty-seventh O2- site, O2- is bonded in a 1-coordinate geometry to one Rb1+, one Th4+, and one Si4+ atom. In the twenty-eighth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the twenty-ninth O2- site, O2- is bonded in a linear geometry to two Si4+ atoms. In the thirtieth O2- site, O2- is bonded in a 1-coordinate geometry to two Rb1+, one Th4+, and one Si4+ atom.

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2020-04-29. Materials Data on Rb2Th(Si2O5)3 by Materials Project. https://doi.org/10.17188/1667249

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