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DOE OSTI · 1754112

Materials Data on Eu2Si4Pd3Au by Materials Project

Abstract

Eu2Pd3AuSi4 crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. Eu+2.50+ is bonded to eight Si4- atoms to form EuSi8 hexagonal bipyramids that share corners with four equivalent AuSi4 tetrahedra, corners with twelve PdSi4 tetrahedra, edges with four equivalent EuSi8 hexagonal bipyramids, edges with two equivalent AuSi4 tetrahedra, edges with six PdSi4 tetrahedra, and faces with four equivalent EuSi8 hexagonal bipyramids. There are four shorter (3.24 Å) and four longer (3.26 Å) Eu–Si bond lengths. There are two inequivalent Pd2+ sites. In the first Pd2+ site, Pd2+ is bonded to four equivalent Si4- atoms to form PdSi4 tetrahedra that share corners with eight equivalent EuSi8 hexagonal bipyramids, corners with four equivalent PdSi4 tetrahedra, edges with four equivalent EuSi8 hexagonal bipyramids, and edges with four equivalent PdSi4 tetrahedra. All Pd–Si bond lengths are 2.48 Å. In the second Pd2+ site, Pd2+ is bonded to four equivalent Si4- atoms to form PdSi4 tetrahedra that share corners with eight equivalent EuSi8 hexagonal bipyramids, corners with four equivalent PdSi4 tetrahedra, edges with four equivalent EuSi8 hexagonal bipyramids, and edges with four equivalent AuSi4 tetrahedra. All Pd–Si bond lengths are 2.53 Å. Au5+ is bonded to four equivalent Si4- atoms to form AuSi4 tetrahedra that share corners with eight equivalent EuSi8 hexagonal bipyramids, corners with four equivalent AuSi4 tetrahedra, edges with four equivalent EuSi8 hexagonal bipyramids, and edges with four equivalent PdSi4 tetrahedra. All Au–Si bond lengths are 2.53 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to four equivalent Eu+2.50+, two equivalent Pd2+, two equivalent Au5+, and one Si4- atom. The Si–Si bond length is 2.36 Å. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to four equivalent Eu+2.50+, four equivalent Pd2+, and one Si4- atom.

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2020-05-02. Materials Data on Eu2Si4Pd3Au by Materials Project. https://doi.org/10.17188/1754112

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36 MATERIALS SCIENCE↗