Materials Data on CsCrAs2O7 by Materials Project
CsCrAs2O7 crystallizes in the monoclinic P2_1/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 3.02–3.48 Å. Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six AsO4 tetrahedra. There are a spread of Cr–O bond distances ranging from 2.00–2.07 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 three equivalent CrO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 27–54°. There are a spread of As–O bond distances ranging from 1.70–1.81 Å. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with three equivalent CrO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 18–47°. There are a spread of As–O bond distances ranging from 1.68–1.81 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Cs1+, one Cr3+, and one As5+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Cs1+, one Cr3+, and one As5+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Cs1+, one Cr3+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Cs1+, one Cr3+, and one As5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Cs1+, one Cr3+, and one As5+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cs1+, one Cr3+, and one As5+ atom. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to one Cs1+ and two As5+ atoms.