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DOE OSTI · 1757270

Materials Data on Ca9Si4O17F by Materials Project

Abstract

Ca9Si4O17F is beta indium sulfide-derived structured and crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are nine inequivalent Ca sites. In the first Ca site, Ca is bonded to five O and one F atom to form distorted CaO5F octahedra that share corners with six CaO5F octahedra, corners with two equivalent SiO4 tetrahedra, edges with three CaO5F octahedra, and an edgeedge with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–69°. There are a spread of Ca–O bond distances ranging from 2.29–2.46 Å. The Ca–F bond length is 2.31 Å. In the second Ca site, Ca is bonded to five O and one F atom to form distorted CaO5F octahedra that share corners with six CaO5F octahedra, corners with two equivalent SiO4 tetrahedra, edges with three CaO5F octahedra, and an edgeedge with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–71°. There are a spread of Ca–O bond distances ranging from 2.30–2.43 Å. The Ca–F bond length is 2.29 Å. In the third Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with four CaO6 octahedra, corners with two SiO4 tetrahedra, edges with four CaO5F octahedra, and edges with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 62–71°. There are a spread of Ca–O bond distances ranging from 2.33–2.43 Å. In the fourth Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with four CaO6 octahedra, corners with two SiO4 tetrahedra, edges with four CaO5F octahedra, and edges with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 61–71°. There are a spread of Ca–O bond distances ranging from 2.34–2.42 Å. In the fifth Ca site, Ca is bonded to six O atoms to form distorted CaO6 octahedra that share corners with eight CaO6 octahedra, corners with four SiO4 tetrahedra, edges with two CaO6 octahedra, and an edgeedge with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–69°. There are a spread of Ca–O bond distances ranging from 2.33–2.49 Å. In the sixth Ca site, Ca is bonded to six O atoms to form distorted CaO6 octahedra that share corners with eight CaO6 octahedra, corners with four SiO4 tetrahedra, edges with two CaO6 octahedra, and an edgeedge with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–70°. There are a spread of Ca–O bond distances ranging from 2.33–2.49 Å. In the seventh Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with four CaO6 octahedra, corners with two SiO4 tetrahedra, edges with four CaO6 octahedra, and edges with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 62–70°. There are a spread of Ca–O bond distances ranging from 2.33–2.42 Å. In the eighth Ca site, Ca is bonded to six O atoms to form distorted CaO6 octahedra that share corners with eight CaO5F octahedra, corners with three SiO4 tetrahedra, edges with two CaO5F octahedra, and an edgeedge with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–71°. There are a spread of Ca–O bond distances ranging from 2.31–2.52 Å. In the ninth Ca site, Ca is bonded to five O and one F atom to form distorted CaO5F octahedra that share corners with eight CaO5F octahedra, corners with three SiO4 tetrahedra, edges with two CaO5F octahedra, and an edgeedge with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–71°. There are a spread of Ca–O bond distances ranging from 2.34–2.50 Å. The Ca–F bond length is 2.28 Å. There are four inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with six CaO6 octahedra and edges with three CaO6 octahedra. The corner-sharing octahedra tilt angles range from 50–60°. There are a spread of Si–O bond distances ranging from 1.64–1.67 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with six CaO6 octahedra and edges with three CaO6 octahedra. The corner-sharing octahedra tilt angles range from 50–60°. There are a spread of Si–O bond distances ranging from 1.64–1.67 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with six CaO5F octahedra and edges with three CaO5F octahedra. The corner-sharing octahedra tilt angles range from 49–60°. There are a spread of Si–O bond distances ranging from 1.64–1.67 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with six CaO5F octahedra and edges with three CaO5F octahedra. The corner-sharing octahedra tilt angles range from 49–59°. There are a spread of Si–O bond distances ranging from 1.64–1.67 Å. There are seventeen inequivalent O sites. In the first O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the second O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the third O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the fourth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the fifth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the sixth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the seventh O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the eighth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the ninth O site, O is bonded in a 4-coordinate geometry to three Ca and one Si atom. In the tenth O site, O is bonded in a 4-coordinate geometry to three Ca and one Si atom. In the eleventh O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the twelfth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the thirteenth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the fourteenth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Si atom. In the fifteenth O site, O is bonded in a 4-coordinate geometry to three Ca and one Si atom. In the sixteenth O site, O is bonded in a 4-coordinate geometry to three Ca and one Si atom. In the seventeenth O site, O is bonded in a distorted trigonal planar geometry to three Ca atoms. F is bonded in a distorted trigonal planar geometry to three Ca atoms.

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2020-09-03. Materials Data on Ca9Si4O17F by Materials Project. https://doi.org/10.17188/1757270

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