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DOE OSTI · 1740736

Materials Data on Ba6NaNd(SiO4)4 by Materials Project

Abstract

NaBa6Nd(SiO4)4 crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.33–2.45 Å. There are six inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.69–3.09 Å. In the second Ba2+ site, Ba2+ is bonded in a 1-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.57–3.06 Å. In the third Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.70–3.28 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 1-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.56–3.31 Å. In the fifth Ba2+ site, Ba2+ is bonded in a 1-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.55–3.29 Å. In the sixth Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.62–3.15 Å. Nd3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Nd–O bond distances ranging from 2.38–2.66 Å. There are four 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 NaO6 octahedra. The corner-sharing octahedral tilt angles are 12°. There is two shorter (1.63 Å) and two longer (1.69 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO6 octahedra. The corner-sharing octahedral tilt angles are 22°. There are a spread of Si–O bond distances ranging from 1.64–1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent NaO6 octahedra. The corner-sharing octahedral tilt angles are 18°. There is one shorter (1.64 Å) and three longer (1.66 Å) Si–O bond length. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent NaO6 octahedra. The corner-sharing octahedral tilt angles are 20°. There are a spread of Si–O bond distances ranging from 1.63–1.71 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three Ba2+, two equivalent Nd3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one Nd3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Ba2+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to four Ba2+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to three Ba2+, two equivalent Nd3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to five Ba2+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, four Ba2+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, four Ba2+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to five Ba2+ and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, four Ba2+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 1-coordinate geometry to four Ba2+ and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, four Ba2+, and one Si4+ atom.

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2020-05-02. Materials Data on Ba6NaNd(SiO4)4 by Materials Project. https://doi.org/10.17188/1740736

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