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DOE OSTI · 1273009

Materials Data on K3EuSi3(HO5)2 by Materials Project

Abstract

K3EuSi3(HO5)2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 1-coordinate geometry to two equivalent H1+ and nine O2- atoms. Both K–H bond lengths are 2.98 Å. There are a spread of K–O bond distances ranging from 2.74–3.37 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of K–O bond distances ranging from 2.79–3.04 Å. Eu3+ is bonded to six O2- atoms to form EuO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Eu–O bond distances ranging from 2.26–2.47 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent EuO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 4–55°. There are a spread of Si–O bond distances ranging from 1.60–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent EuO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–48°. There are a spread of Si–O bond distances ranging from 1.61–1.69 Å. H1+ is bonded in a single-bond geometry to one K1+ and one O2- atom. The H–O bond length is 1.01 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three K1+, one Eu3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Eu3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two K1+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+, one Eu3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to three equivalent K1+, one Si4+, and one H1+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one Eu3+, and one Si4+ atom.

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2020-04-30. Materials Data on K3EuSi3(HO5)2 by Materials Project. https://doi.org/10.17188/1273009

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