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DOE OSTI · 1679076

Materials Data on EuGaAg4 by Materials Project

Abstract

EuAg4Ga crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Eu is bonded in a 6-coordinate geometry to fourteen Ag and four equivalent Ga atoms. There are a spread of Eu–Ag bond distances ranging from 3.25–3.63 Å. All Eu–Ga bond lengths are 3.74 Å. There are two inequivalent Ag sites. In the first Ag site, Ag is bonded in a 12-coordinate geometry to three equivalent Eu, seven Ag, and two equivalent Ga atoms. There are a spread of Ag–Ag bond distances ranging from 2.86–3.41 Å. Both Ag–Ga bond lengths are 2.76 Å. In the second Ag site, Ag is bonded to four equivalent Eu, six Ag, and two equivalent Ga atoms to form AgEu4Ga2Ag6 cuboctahedra that share corners with four equivalent GaEu4Ag8 cuboctahedra, corners with twelve equivalent AgEu4Ga2Ag6 cuboctahedra, edges with four equivalent GaEu4Ag8 cuboctahedra, edges with six equivalent AgEu4Ga2Ag6 cuboctahedra, faces with four equivalent GaEu4Ag8 cuboctahedra, and faces with six equivalent AgEu4Ga2Ag6 cuboctahedra. Both Ag–Ag bond lengths are 2.96 Å. Both Ag–Ga bond lengths are 2.82 Å. Ga is bonded to four equivalent Eu and eight Ag atoms to form distorted GaEu4Ag8 cuboctahedra that share corners with eight equivalent AgEu4Ga2Ag6 cuboctahedra, corners with eight equivalent GaEu4Ag8 cuboctahedra, edges with two equivalent GaEu4Ag8 cuboctahedra, edges with eight equivalent AgEu4Ga2Ag6 cuboctahedra, faces with two equivalent GaEu4Ag8 cuboctahedra, and faces with eight equivalent AgEu4Ga2Ag6 cuboctahedra.

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2020-05-04. Materials Data on EuGaAg4 by Materials Project. https://doi.org/10.17188/1679076

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36 MATERIALS SCIENCE↗