Materials Data on KAsW2O9 by Materials Project
KW2AsO9 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.67–3.03 Å. There are two inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to six O2- atoms to form distorted WO6 octahedra that share corners with four WO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 24–40°. There are a spread of W–O bond distances ranging from 1.76–2.20 Å. In the second W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two equivalent WO6 octahedra and corners with three equivalent AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 24–40°. There are a spread of W–O bond distances ranging from 1.76–2.18 Å. As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with four WO6 octahedra. The corner-sharing octahedra tilt angles range from 28–53°. There are a spread of As–O bond distances ranging from 1.70–1.74 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one W6+ and one As5+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent K1+ and one W6+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, one W6+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one W6+, and one As5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two equivalent W6+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and one W6+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two W6+ atoms. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to two W6+ atoms. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one W6+ and one As5+ atom.