Materials Data on CsAs3O8 by Materials Project
CsAs3O8 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Cs1+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Cs–O bond distances ranging from 3.16–3.49 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to six O2- atoms to form AsO6 octahedra that share corners with two equivalent AsO4 tetrahedra and edges with two equivalent AsO6 octahedra. There are a spread of As–O bond distances ranging from 1.82–1.96 Å. In the second As5+ site, As5+ is bonded to four O2- atoms to form corner-sharing AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–60°. All As–O bond lengths are 1.73 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Cs1+ and two equivalent As5+ atoms. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cs1+ and two As5+ atoms. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cs1+ and two As5+ atoms. In the fourth O2- site, O2- is bonded in an L-shaped geometry to one Cs1+ and two equivalent As5+ atoms.