DOE OSTI2020
LaAg3Al2 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. La is bonded in a 6-coordinate geometry to ten Ag and eight equivalent Al atoms. There are a spread of La–Ag bond distances ranging from 3.17–3.59 Å. All La–Al bond lengths are 3.62 Å. There are two inequivalent Ag sites. In the first Ag site, Ag is bonded to four equivalent La, four equivalent Ag, and four equivalent Al atoms to form distorted AgLa4Al4Ag4 cuboctahedra that share corners with eight equivalent AgLa4Al4Ag4 cuboctahedra, corners with eight equivalent AlLa4Al2Ag6 cuboctahedra, edges with two equivalent AgLa4Al4Ag4 cuboctahedra, edges with eight equivalent AlLa4Al2Ag6 cuboctahedra, faces with two equivalent AgLa4Al4Ag4 cuboctahedra, and faces with eight equivalent AlLa4Al2Ag6 cuboctahedra. All Ag–Ag bond lengths are 2.85 Å. All Ag–Al bond lengths are 2.80 Å. In the second Ag site, Ag is bonded in a 12-coordinate geometry to three equivalent La, two equivalent Ag, and four equivalent Al atoms. All Ag–Al bond lengths are 2.77 Å. Al is bonded to four equivalent La, six Ag, and two equivalent Al atoms to form distorted AlLa4Al2Ag6 cuboctahedra that share corners with four equivalent AgLa4Al4Ag4 cuboctahedra, corners with twelve equivalent AlLa4Al2Ag6 cuboctahedra, edges with four equivalent AgLa4Al4Ag4 cuboctahedra, edges with six equivalent AlLa4Al2Ag6 cuboctahedra, faces with four equivalent AgLa4Al4Ag4 cuboctahedra, and faces with six equivalent AlLa4Al2Ag6 cuboctahedra. Both Al–Al bond lengths are 2.76 Å.