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DOE OSTI · 1757227

Materials Data on Al2SiAg7 by Materials Project

Abstract

Ag7Al2Si crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are seven inequivalent Ag sites. In the first Ag site, Ag is bonded in a 12-coordinate geometry to eight Ag, three Al, and one Si atom. There are a spread of Ag–Ag bond distances ranging from 2.91–3.01 Å. There are a spread of Ag–Al bond distances ranging from 2.85–2.98 Å. The Ag–Si bond length is 2.80 Å. In the second Ag site, Ag is bonded in a 12-coordinate geometry to eight Ag, three Al, and one Si atom. There are a spread of Ag–Ag bond distances ranging from 2.91–2.97 Å. There are a spread of Ag–Al bond distances ranging from 2.80–3.06 Å. The Ag–Si bond length is 2.95 Å. In the third Ag site, Ag is bonded in a 12-coordinate geometry to seven Ag, three Al, and two equivalent Si atoms. There are a spread of Ag–Ag bond distances ranging from 2.90–2.95 Å. There are a spread of Ag–Al bond distances ranging from 2.81–3.02 Å. There are one shorter (2.83 Å) and one longer (2.99 Å) Ag–Si bond lengths. In the fourth Ag site, Ag is bonded in a 12-coordinate geometry to seven Ag, three Al, and two equivalent Si atoms. There are a spread of Ag–Ag bond distances ranging from 2.91–2.96 Å. There are a spread of Ag–Al bond distances ranging from 2.79–3.01 Å. There are one shorter (2.96 Å) and one longer (2.99 Å) Ag–Si bond lengths. In the fifth Ag site, Ag is bonded in a 12-coordinate geometry to seven Ag, three Al, and two equivalent Si atoms. There are one shorter (2.97 Å) and one longer (3.00 Å) Ag–Ag bond lengths. There are a spread of Ag–Al bond distances ranging from 2.82–3.01 Å. There are one shorter (2.85 Å) and one longer (2.94 Å) Ag–Si bond lengths. In the sixth Ag site, Ag is bonded in a 12-coordinate geometry to eight Ag, three Al, and one Si atom. There are one shorter (2.91 Å) and one longer (2.97 Å) Ag–Ag bond lengths. There are a spread of Ag–Al bond distances ranging from 2.78–3.03 Å. The Ag–Si bond length is 2.92 Å. In the seventh Ag site, Ag is bonded in a distorted trigonal planar geometry to nine Ag and three Al atoms. There are one shorter (2.62 Å) and two longer (2.64 Å) Ag–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded to ten Ag and two equivalent Si atoms to form a mixture of distorted face and corner-sharing AlSi2Ag10 cuboctahedra. There are one shorter (2.63 Å) and one longer (2.64 Å) Al–Si bond lengths. In the second Al site, Al is bonded to eleven Ag and one Si atom to form a mixture of distorted face and corner-sharing AlSiAg11 cuboctahedra. The Al–Si bond length is 2.61 Å. Si is bonded in a 12-coordinate geometry to nine Ag and three Al atoms.

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2020-09-03. Materials Data on Al2SiAg7 by Materials Project. https://doi.org/10.17188/1757227

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36 MATERIALS SCIENCE↗