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DOE OSTI · 1718427

Materials Data on Na2Be3Si3O8 by Materials Project

Abstract

Na2Be3Si3O8 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded in a 3-coordinate geometry to one Be and two O atoms. The Na–Be bond length is 3.09 Å. There are one shorter (2.46 Å) and one longer (2.49 Å) Na–O bond lengths. In the second Na site, Na is bonded in a 4-coordinate geometry to one Be and three O atoms. The Na–Be bond length is 2.83 Å. There are a spread of Na–O bond distances ranging from 2.42–2.79 Å. There are three inequivalent Be sites. In the first Be site, Be is bonded in an L-shaped geometry to two equivalent Be and two O atoms. There are one shorter (2.22 Å) and one longer (2.23 Å) Be–Be bond lengths. Both Be–O bond lengths are 1.65 Å. In the second Be site, Be is bonded in a 5-coordinate geometry to two Na and three Be atoms. The Be–Be bond length is 1.91 Å. In the third Be site, Be is bonded to four O atoms to form distorted BeO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.53–1.74 Å. There are three 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 BeO4 tetrahedra and corners with two equivalent SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.59–1.68 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 SiO4 tetrahedra that share corners with two equivalent BeO4 tetrahedra and corners with two equivalent SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.58–1.69 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to two Be and one Si atom. In the second O site, O is bonded in a bent 150 degrees geometry to one Be and one Si atom. In the third O site, O is bonded in a distorted rectangular see-saw-like geometry to one Na, two Be, and one Si atom. In the fourth O site, O is bonded in a distorted T-shaped geometry to one Na and two Si atoms. In the fifth O site, O is bonded in a 3-coordinate geometry to one Na, one Be, and one Si atom. In the sixth O site, O is bonded in a 3-coordinate geometry to one Na and two Si atoms. In the seventh O site, O is bonded in a distorted bent 150 degrees geometry to two Si atoms. In the eighth O site, O is bonded in a 2-coordinate geometry to one Na and two Si atoms.

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2020-05-02. Materials Data on Na2Be3Si3O8 by Materials Project. https://doi.org/10.17188/1718427

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