DOE OSTI2020
K4Ba(VO3)6 crystallizes in the trigonal R3c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.88 Å) and three longer (2.99 Å) K–O bond lengths. In the second K1+ site, K1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.84–3.36 Å. Ba2+ is bonded to twelve O2- atoms to form distorted BaO12 cuboctahedra that share edges with six VO4 tetrahedra. There are a spread of Ba–O bond distances ranging from 2.82–3.36 Å. There are two inequivalent V5+ sites. In the first V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with two equivalent VO4 tetrahedra and an edgeedge with one BaO12 cuboctahedra. There are a spread of V–O bond distances ranging from 1.67–1.81 Å. In the second V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with two equivalent VO4 tetrahedra and an edgeedge with one BaO12 cuboctahedra. There is two shorter (1.68 Å) and two longer (1.81 Å) V–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two K1+, one Ba2+, and one V5+ atom. In the second O2- site, O2- is bonded in a linear geometry to two equivalent K1+ and two V5+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+, one Ba2+, and one V5+ atom. In the fourth O2- site, O2- is bonded in a linear geometry to one K1+ and two V5+ atoms. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to two K1+, one Ba2+, and one V5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+, one Ba2+, and one V5+ atom.