DOE OSTI2020
Ba3(LiSb)4 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Li1+ is bonded to four Sb+2.50- atoms to form LiSb4 tetrahedra that share a cornercorner with one BaSb6 octahedra, corners with ten equivalent LiSb4 tetrahedra, edges with two equivalent BaSb6 octahedra, and edges with three equivalent LiSb4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Li–Sb bond distances ranging from 2.99–3.06 Å. There are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six Sb+2.50- atoms. There are two shorter (3.60 Å) and four longer (3.64 Å) Ba–Sb bond lengths. In the second Ba2+ site, Ba2+ is bonded to six Sb+2.50- atoms to form BaSb6 octahedra that share corners with four equivalent LiSb4 tetrahedra, edges with two equivalent BaSb6 octahedra, and edges with eight equivalent LiSb4 tetrahedra. There are four shorter (3.49 Å) and two longer (3.54 Å) Ba–Sb bond lengths. There are two inequivalent Sb+2.50- sites. In the first Sb+2.50- site, Sb+2.50- is bonded in a 6-coordinate geometry to six equivalent Li1+ and three Ba2+ atoms. In the second Sb+2.50- site, Sb+2.50- is bonded in a 2-coordinate geometry to two equivalent Li1+, six Ba2+, and one Sb+2.50- atom. The Sb–Sb bond length is 2.86 Å.