Materials Data on Eu2Al6Si3Au2 by Materials Project

Abstract

Eu2Au2Al6Si3 crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. there are two inequivalent Eu sites. In the first Eu site, Eu is bonded in a 8-coordinate geometry to four equivalent Au, eight Al, and four equivalent Si atoms. All Eu–Au bond lengths are 3.35 Å. There are four shorter (3.40 Å) and four longer (3.43 Å) Eu–Al bond lengths. All Eu–Si bond lengths are 3.37 Å. In the second Eu site, Eu is bonded in a 12-coordinate geometry to eight Al and eight Si atoms. There are four shorter (3.29 Å) and four longer (3.44 Å) Eu–Al bond lengths. There are four shorter (3.31 Å) and four longer (3.38 Å) Eu–Si bond lengths. There are two inequivalent Au sites. In the first Au site, Au is bonded in a body-centered cubic geometry to eight Al atoms. There are four shorter (2.61 Å) and four longer (2.66 Å) Au–Al bond lengths. In the second Au site, Au is bonded in a 9-coordinate geometry to four equivalent Eu, four equivalent Al, and one Si atom. All Au–Al bond lengths are 2.59 Å. The Au–Si bond length is 2.51 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded to two equivalent Eu and four Au atoms to form a mixture of distorted face, edge, and corner-sharing AlEu2Au4 tetrahedra. In the second Al site, Al is bonded to two equivalent Eu, two equivalent Au, and two equivalent Si atoms to form distorted AlEu2Si2Au2 tetrahedra that share corners with fourteen AlEu2Au4 tetrahedra, edges with four AlEu2Au4 tetrahedra, and faces with four equivalent AlEu2Si2Au2 tetrahedra. Both Al–Si bond lengths are 2.58 Å. In the third Al site, Al is bonded to four Eu and four Si atoms to form distorted AlEu4Si4 tetrahedra that share corners with twelve AlEu2Au4 tetrahedra, edges with six AlEu2Au4 tetrahedra, and faces with four equivalent AlEu4Si4 tetrahedra. All Al–Si bond lengths are 2.58 Å. There are three inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to four equivalent Eu, four equivalent Al, and one Si atom. The Si–Si bond length is 2.42 Å. In the second Si site, Si is bonded in a 1-coordinate geometry to four equivalent Eu, one Au, and four equivalent Al atoms. In the third Si site, Si is bonded in a 9-coordinate geometry to four equivalent Eu, four equivalent Al, and one Si atom.