Materials Data on TlZnAsO4 by Materials Project

Abstract

ZnTlAsO4 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with two equivalent TlO8 hexagonal bipyramids, corners with four AsO4 tetrahedra, and an edgeedge with one TlO8 hexagonal bipyramid. There is two shorter (1.98 Å) and two longer (2.00 Å) Zn–O bond length. In the second Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with two equivalent TlO8 hexagonal bipyramids, corners with four AsO4 tetrahedra, and an edgeedge with one TlO8 hexagonal bipyramid. There are a spread of Zn–O bond distances ranging from 1.96–2.00 Å. There are two inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a distorted pentagonal planar geometry to five O2- atoms. There are a spread of Tl–O bond distances ranging from 2.75–3.06 Å. In the second Tl1+ site, Tl1+ is bonded to eight O2- atoms to form distorted TlO8 hexagonal bipyramids that share corners with two equivalent TlO8 hexagonal bipyramids, corners with four ZnO4 tetrahedra, corners with four AsO4 tetrahedra, edges with two equivalent TlO8 hexagonal bipyramids, edges with two ZnO4 tetrahedra, and edges with two AsO4 tetrahedra. There are a spread of Tl–O bond distances ranging from 2.76–3.24 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 TlO8 hexagonal bipyramids, corners with four ZnO4 tetrahedra, and an edgeedge with one TlO8 hexagonal bipyramid. There is one shorter (1.72 Å) and three longer (1.73 Å) As–O bond length. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent TlO8 hexagonal bipyramids, corners with four ZnO4 tetrahedra, and an edgeedge with one TlO8 hexagonal bipyramid. All As–O bond lengths are 1.73 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Zn2+, one Tl1+, and one As5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Zn2+, two Tl1+, and one As5+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Zn2+, two equivalent Tl1+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Zn2+, one Tl1+, and one As5+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Zn2+, two Tl1+, and one As5+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Zn2+, two equivalent Tl1+, and one As5+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Zn2+, two equivalent Tl1+, and one As5+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Zn2+, one Tl1+, and one As5+ atom.