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DOE OSTI · 1708545

Materials Data on MgAg3 by Materials Project

Abstract

Ag3Mg crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Mg is bonded to six equivalent Ag atoms to form distorted MgAg6 cuboctahedra that share corners with six equivalent AgAg12 cuboctahedra, edges with six equivalent MgAg6 cuboctahedra, and edges with six equivalent AgAg12 cuboctahedra. All Mg–Ag bond lengths are 2.90 Å. There are five inequivalent Ag sites. In the first Ag site, Ag is bonded to three equivalent Mg and three equivalent Ag atoms to form a mixture of distorted edge and corner-sharing AgMg3Ag3 cuboctahedra. All Ag–Ag bond lengths are 2.93 Å. In the second Ag site, Ag is bonded to twelve Ag atoms to form AgAg12 cuboctahedra that share corners with six equivalent MgAg6 cuboctahedra, corners with eighteen AgMg3Ag3 cuboctahedra, edges with six equivalent MgAg6 cuboctahedra, edges with eighteen AgMg3Ag3 cuboctahedra, and faces with six equivalent AgAg12 cuboctahedra. All Ag–Ag bond lengths are 3.04 Å. In the third Ag site, Ag is bonded to three equivalent Mg and three equivalent Ag atoms to form distorted AgMg3Ag3 cuboctahedra that share corners with fourteen AgMg3Ag3 cuboctahedra, edges with twenty AgMg3Ag3 cuboctahedra, and faces with two equivalent AgAg16 cuboctahedra. All Ag–Mg bond lengths are 2.90 Å. All Ag–Ag bond lengths are 2.93 Å. In the fourth Ag site, Ag is bonded to sixteen Ag atoms to form AgAg16 cuboctahedra that share corners with six equivalent MgAg6 cuboctahedra, corners with twenty-two AgMg3Ag3 cuboctahedra, edges with six equivalent MgAg6 cuboctahedra, edges with twenty-six AgMg3Ag3 cuboctahedra, and faces with twenty AgMg3Ag3 cuboctahedra. There are a spread of Ag–Ag bond distances ranging from 2.93–6.08 Å. In the fifth Ag site, Ag is bonded to three equivalent Mg and three equivalent Ag atoms to form distorted AgMg3Ag3 cuboctahedra that share corners with fourteen AgMg3Ag3 cuboctahedra, edges with twenty AgMg3Ag3 cuboctahedra, and faces with two equivalent AgAg16 cuboctahedra. All Ag–Mg bond lengths are 2.90 Å.

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2020-05-03. Materials Data on MgAg3 by Materials Project. https://doi.org/10.17188/1708545

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