Materials Data on KZr2(AsO4)3 by Materials Project
KZr2(AsO4)3 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. K1+ is bonded in a hexagonal planar geometry to six equivalent O2- atoms. All K–O bond lengths are 2.87 Å. Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with six equivalent AsO4 tetrahedra. There are three shorter (2.09 Å) and three longer (2.12 Å) Zr–O bond lengths. As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with four equivalent ZrO6 octahedra. The corner-sharing octahedral tilt angles are 30°. All As–O bond lengths are 1.71 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Zr4+ and one As5+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Zr4+, and one As5+ atom.