Materials Data on EuAlAg4 by Materials Project
EuAg4Al crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Eu is bonded in a 6-coordinate geometry to fifteen Ag and three equivalent Al atoms. There are three shorter (3.36 Å) and twelve longer (3.65 Å) Eu–Ag bond lengths. All Eu–Al bond lengths are 3.36 Å. There are two inequivalent Ag sites. In the first Ag site, Ag is bonded to three equivalent Eu and six equivalent Ag atoms to form distorted AgEu3Ag6 cuboctahedra that share corners with eighteen AgEu3Ag6 cuboctahedra, edges with twelve equivalent AgEu4Al2Ag6 cuboctahedra, and faces with eight AgEu3Ag6 cuboctahedra. All Ag–Ag bond lengths are 2.79 Å. In the second Ag site, Ag is bonded to four equivalent Eu, six Ag, and two equivalent Al atoms to form a mixture of distorted edge, face, and corner-sharing AgEu4Al2Ag6 cuboctahedra. There are two shorter (2.85 Å) and two longer (2.97 Å) Ag–Ag bond lengths. Both Ag–Al bond lengths are 2.75 Å. Al is bonded in a 12-coordinate geometry to three equivalent Eu and six equivalent Ag atoms.