Materials Data on K3Bi2(AsO4)3 by Materials Project
K3Bi2(AsO4)3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.77–3.08 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.73–3.08 Å. In the third K1+ site, K1+ is bonded to six O2- atoms to form KO6 octahedra that share corners with two equivalent BiO6 octahedra, corners with six AsO4 tetrahedra, and edges with two equivalent KO6 octahedra. The corner-sharing octahedral tilt angles are 81°. There are a spread of K–O bond distances ranging from 2.70–2.86 Å. Bi3+ is bonded to six O2- atoms to form distorted BiO6 octahedra that share a cornercorner with one KO6 octahedra, corners with six AsO4 tetrahedra, and an edgeedge with one BiO6 octahedra. The corner-sharing octahedral tilt angles are 81°. There are a spread of Bi–O bond distances ranging from 2.27–2.58 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent KO6 octahedra and corners with four equivalent BiO6 octahedra. The corner-sharing octahedra tilt angles range from 19–66°. There are a spread of As–O bond distances ranging from 1.70–1.75 Å. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent KO6 octahedra and corners with four equivalent BiO6 octahedra. The corner-sharing octahedra tilt angles range from 46–60°. There is two shorter (1.71 Å) and two longer (1.75 Å) As–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one As5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Bi3+ and one As5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one Bi3+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one Bi3+, and one As5+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one Bi3+, and one As5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent K1+, one Bi3+, and one As5+ atom.