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DOE OSTI · 1269378

Materials Data on Sr10Al4Si6O by Materials Project

Abstract

Sr10Al4Si6O crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are five inequivalent Sr sites. In the first Sr site, Sr is bonded in a distorted single-bond geometry to five Si and one O atom. There are four shorter (3.42 Å) and one longer (3.66 Å) Sr–Si bond lengths. The Sr–O bond length is 2.89 Å. In the second Sr site, Sr is bonded in a single-bond geometry to four equivalent Al, four equivalent Si, and one O atom. All Sr–Al bond lengths are 3.44 Å. All Sr–Si bond lengths are 3.44 Å. The Sr–O bond length is 2.50 Å. In the third Sr site, Sr is bonded in a 7-coordinate geometry to two equivalent Al and five Si atoms. Both Sr–Al bond lengths are 3.32 Å. There are a spread of Sr–Si bond distances ranging from 3.24–3.41 Å. In the fourth Sr site, Sr is bonded in a linear geometry to four equivalent Si and two equivalent O atoms. All Sr–Si bond lengths are 3.41 Å. Both Sr–O bond lengths are 2.42 Å. In the fifth Sr site, Sr is bonded to eight equivalent Al and four equivalent Si atoms to form face-sharing SrAl8Si4 cuboctahedra. All Sr–Al bond lengths are 3.46 Å. All Sr–Si bond lengths are 3.62 Å. Al is bonded in a distorted bent 120 degrees geometry to six Sr, one Al, and two Si atoms. The Al–Al bond length is 2.61 Å. There are one shorter (2.47 Å) and one longer (2.52 Å) Al–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to eight Sr and one Al atom. In the second Si site, Si is bonded in a 2-coordinate geometry to seven Sr and two equivalent Al atoms. O is bonded to six Sr atoms to form corner-sharing OSr6 octahedra. The corner-sharing octahedral tilt angles are 0°.

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2020-07-23. Materials Data on Sr10Al4Si6O by Materials Project. https://doi.org/10.17188/1269378

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36 MATERIALS SCIENCE↗