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DOE OSTI · 1749174

Materials Data on Ca5(Si3O11)2 by Materials Project

Abstract

Ca5(Si3O11)2 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are five inequivalent Ca sites. In the first Ca site, Ca is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.94 Å. In the second Ca site, Ca is bonded to seven O atoms to form distorted CaO7 hexagonal pyramids that share corners with four SiO4 tetrahedra and an edgeedge with one SiO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.35–2.49 Å. In the third Ca site, Ca is bonded in a 5-coordinate geometry to seven O atoms. There are a spread of Ca–O bond distances ranging from 2.39–2.85 Å. In the fourth Ca site, Ca is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Ca–O bond distances ranging from 2.40–2.67 Å. In the fifth Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.26–2.65 Å. There are six inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent CaO7 hexagonal pyramids and corners with two SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the second Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the third Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the fourth Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent CaO7 hexagonal pyramids and corners with two SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.69 Å. In the sixth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two SiO4 tetrahedra and an edgeedge with one CaO7 hexagonal pyramid. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. There are twenty-two inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to one Ca and two Si atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the third O site, O is bonded in a bent 120 degrees geometry to two Si atoms. In the fourth O site, O is bonded in a distorted bent 150 degrees geometry to two Si atoms. In the fifth O site, O is bonded to three Ca and one Si atom to form a mixture of distorted edge and corner-sharing OCa3Si tetrahedra. In the sixth O site, O is bonded to three Ca and one Si atom to form distorted edge-sharing OCa3Si tetrahedra. In the seventh O site, O is bonded in a 4-coordinate geometry to three Ca and one Si atom. In the eighth O site, O is bonded in a 4-coordinate 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 1-coordinate geometry to three Ca and one Si atom. In the twelfth O site, O is bonded to three Ca and one Si atom to form a mixture of distorted edge and corner-sharing OCa3Si tetrahedra. In the thirteenth O site, O is bonded in a 3-coordinate geometry to one Ca and two Si atoms. In the fourteenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fifteenth O site, O is bonded in a linear geometry to two Si atoms. In the sixteenth O site, O is bonded in a single-bond geometry to one Ca atom. In the seventeenth O site, O is bonded in a distorted trigonal planar geometry to two Ca and one Si atom. In the eighteenth O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and one Si atom. In the nineteenth O site, O is bonded in a single-bond geometry to one Ca atom. In the twentieth O site, O is bonded in a bent 150 degrees geometry to one Ca and one O atom. The O–O bond length is 1.23 Å. In the twenty-first O site, O is bonded in a single-bond geometry to one Ca atom. In the twenty-second O site, O is bonded in a water-like geometry to one Ca and one O atom.

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2020-05-02. Materials Data on Ca5(Si3O11)2 by Materials Project. https://doi.org/10.17188/1749174

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