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DOE OSTI · 1758147

Materials Data on CaMgB6O17 by Materials Project

Abstract

CaMgB6O17 crystallizes in the monoclinic P2/c space group. The structure is three-dimensional. Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.68 Å. Mg is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Mg–O bond distances ranging from 1.98–2.69 Å. There are three inequivalent B sites. In the first B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There is two shorter (1.46 Å) and two longer (1.50 Å) B–O bond length. In the second B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.43–1.57 Å. In the third B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.36–1.41 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and two B atoms. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and two B atoms. In the third O site, O is bonded in a distorted single-bond geometry to one Ca and one B atom. In the fourth O site, O is bonded in a distorted trigonal non-coplanar geometry to one Ca, one B, and one O atom. The O–O bond length is 1.40 Å. In the fifth O site, O is bonded in a 2-coordinate geometry to two equivalent Mg and two equivalent O atoms. Both O–O bond lengths are 1.77 Å. In the sixth O site, O is bonded in a bent 120 degrees geometry to one Mg and one O atom. The O–O bond length is 1.23 Å. In the seventh O site, O is bonded in a distorted bent 150 degrees geometry to one Mg, one B, and one O atom. In the eighth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the ninth O site, O is bonded in a bent 120 degrees geometry to two B atoms.

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2020-09-03. Materials Data on CaMgB6O17 by Materials Project. https://doi.org/10.17188/1758147

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36 MATERIALS SCIENCE↗