Materials Data on Eu2(AlAg)5 by Materials Project

Abstract

Eu2(AgAl)5 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. there are two inequivalent Eu sites. In the first Eu site, Eu is bonded in a distorted hexagonal planar geometry to six Ag and twelve Al atoms. There are two shorter (3.20 Å) and four longer (3.22 Å) Eu–Ag bond lengths. There are four shorter (3.57 Å) and eight longer (3.62 Å) Eu–Al bond lengths. In the second Eu site, Eu is bonded in a 6-coordinate geometry to ten Ag and eight equivalent Al atoms. There are a spread of Eu–Ag bond distances ranging from 3.26–3.57 Å. All Eu–Al bond lengths are 3.61 Å. There are three inequivalent Ag sites. In the first Ag site, Ag is bonded in a 12-coordinate geometry to three Eu, two equivalent Ag, and four equivalent Al atoms. Both Ag–Ag bond lengths are 2.84 Å. All Ag–Al bond lengths are 2.75 Å. In the second Ag site, Ag is bonded in a 12-coordinate geometry to three Eu and six Al atoms. There are four shorter (2.78 Å) and two longer (2.79 Å) Ag–Al bond lengths. In the third Ag site, Ag is bonded to four equivalent Eu, four equivalent Ag, and four equivalent Al atoms to form distorted AgEu4Al4Ag4 cuboctahedra that share corners with four equivalent AgEu4Al4Ag4 cuboctahedra, corners with four equivalent AlEu4Al4Ag4 cuboctahedra, edges with two equivalent AgEu4Al4Ag4 cuboctahedra, and faces with two equivalent AgEu4Al4Ag4 cuboctahedra. All Ag–Al bond lengths are 2.81 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to four equivalent Eu, four equivalent Ag, and four equivalent Al atoms to form distorted AlEu4Al4Ag4 cuboctahedra that share corners with four equivalent AgEu4Al4Ag4 cuboctahedra, corners with four equivalent AlEu4Al4Ag4 cuboctahedra, edges with two equivalent AlEu4Al4Ag4 cuboctahedra, and faces with two equivalent AlEu4Al4Ag4 cuboctahedra. All Al–Al bond lengths are 2.83 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to four Eu, five Ag, and three Al atoms. There are one shorter (2.76 Å) and one longer (2.77 Å) Al–Al bond lengths.